Monday, 30 June 2014

Hill Lists – Cymru / Wales – 200m Twmpau updates – Bryniau Dyfi



The first list to the Welsh 200m P30 hills was published on Geoff Crowder’s website v-g.me in 2000; this list preceded the list of TuMPs by nine years, the list proved a very useful resource for the TuMP compilation for this category of hill.

The Welsh 200m P30 list documents all hills in Wales that are at or above 200m in height and are below 300m in height, to qualify for the main list each hill requires a minimum of 30m of prominence.


The hills listed below are updates to the Welsh 200m P30 list originally published on Geoff Crowder's website.  To see the original list click {here}


The original published list had a Sub-List which was entitled ‘Hills to Survey’.  This list consisted of all hills in Wales in the stipulated height band that have a minimum of 20m of prominence, but do not meet the minimum 30m of prominence to enter the main list, according to Ordnance Survey map spot heights and contours.  Nowadays the standard Sub-List takes in all hills that have a minimum of 20m of prominence.  However, the Hills to Survey Sub-List discounted hills whose map spot heights gave a drop value of less than 30m, but more than 20m.  By doing so, the only hills that were Sub-Listed were those that map values dictated stood a chance of entering the main list, for example; if a hill had a summit spot height of 250m and a bwlch spot height of 221m, it was not listed in the Hills to Survey Sub-List as with 29m of drop I thought it did not stand a chance of main list qualification. 

When compiling the Sub-List I was measuring many hills for P30 status using a basic levelling technique, please click {here} for more information concerning this.  I now know that Ordnance Survey spot heights have a standard margin of uncertainty of + / - 3m associated with their accuracy.  Therefore many hills that were not listed in the original Sub-List may have sufficient drop to enter the main list.  Because of this the Sub-List has been altered to include all hills that have a minimum of 20m of drop but are not known to attain the minimum 30m of drop to enter the main list.

The hills listed below are those major amendments to the original Welsh 200m P30 list as it appears on Geoff’s website.  There are many hills that have been promoted from the Hills to Survey Sub-List to the main list, whilst there are many additions to the Sub-List now that it has been standardised to include all 20m minimum but below 30m drop hills.

When the 200m P30 list was first published it was the first to this category of hills and in some way it and its other 100m height band lists paved the way for Clem’s data that later appeared on the RHB file database and then for the TuMPs listing by Mark Jackson.

As well as the first P30 list to this height band the list is now the first to include a comprehensive Sub-List.

TuMP baggers beware; as the main list also includes P30’s not listed by Mark Jackson, so if you want to visit all P30’s you’ll have to include some non TuMPs to do so.

The list will be updated on a weekly basis and will be done so through each Group category, starting from the north and working south.  The twelfth Group is Bryniau Dyfi.



Bryniau Dyfi 

North and then west of the Afon Dyfi (River Dovey) from SH 753 018 to SH 861 149, continuing south of the Afon Cerist to Bwlch Oerddrws at SH 802 170 and the Nant Tyn-twll to SH 767 167, continuing east of the Afon Clywedog to bwlch at SH 756 139 and the Nant yr Allt-oen and the Afon Fawnog and Afon Faw to Llyn Mwyngil (Tal y Llyn Lake) at SH 720 103, continuing east from stream at SH 724 102 to bwlch at SH 737 093 and following stream to SH 757 077 and the Afon Dulas to SH 753 018.  Bordering with the Aran to the north, Cadair Idris and Tarennydd to the west, Pumlumon to the south and Mynydd y Cemaes and Y Berwyn to the east.    



Twmpau - 200m updates

Mynydd Llwyn-gwern    276m    SH 766 045

This hill is promoted from the Sub-List as Harvey Maps have a 276m summit spot height, no spot height can be found on any Ordnance Survey map for the summit.  The bwlch has a 242m spot height on the Ordnance Survey enlarged Geograph map, giving this hill 34m of drop.



Sub-Twmpau - 100m updates

Cefn Llandybo    259m    SH 835 098

This hill has a 259m summit and 235m bwlch spot height on the Ordnance Survey 1:25,000 Explorer map as well as the enlarged Geograph map, giving this hill 24m of drop.



Pt. 247m    247m    SH 829 074

The Ordnance Survey enlarged Geograph map give this hill a summit spot height of 247m and a bwlch spot height of 226m, giving this hill 21m of drop.



Pt. 259m    259m    SH 789 047

This hill follows the Pt. notation as the blog author does not know an appropriate name for it.  It has a 259m summit spot height on the Ordnance Survey 1:25,000 Explorer map as well as the enlarged Geograph map, whilst the latter map gives a spot height on the area of the bwlch of 239m, giving this hill 20m of drop.




Next update due on the 7th July 2014

Monday, 23 June 2014

Hill Lists – Cymru / Wales – 200m twmpau updates – Carnedd Wen



The first list to the Welsh 200m P30 hills was published on Geoff Crowder’s website v-g.me in 2000; this list preceded the list of TuMPs by nine years, the list proved a very useful resource for the TuMP compilation for this category of hill.

The Welsh 200m P30 list documents all hills in Wales that are at or above 200m in height and are below 300m in height, to qualify for the main list each hill requires a minimum of 30m of prominence.


The hills listed below are updates to the Welsh 200m P30 list originally published on Geoff Crowder's website.  To see the original list click {here}


The original published list had a Sub-List which was entitled ‘Hills to Survey’.  This list consisted of all hills in Wales in the stipulated height band that have a minimum of 20m of prominence, but do not meet the minimum 30m of prominence to enter the main list, according to Ordnance Survey map spot heights and contours.  Nowadays the standard Sub-List takes in all hills that have a minimum of 20m of prominence.  However, the Hills to Survey Sub-List discounted hills whose map spot heights gave a drop value of less than 30m, but more than 20m.  By doing so, the only hills that were Sub-Listed were those that map values dictated stood a chance of entering the main list, for example; if a hill had a summit spot height of 250m and a bwlch spot height of 221m, it was not listed in the Hills to Survey Sub-List as with 29m of drop I thought it did not stand a chance of main list qualification.
 
When compiling the Sub-List I was measuring many hills for P30 status using a basic levelling technique, please click {here} for more information concerning this.  I now know that Ordnance Survey spot heights have a standard margin of uncertainty of + / - 3m associated with their accuracy.  Therefore many hills that were not listed in the original Sub-List may have sufficient drop to enter the main list.  Because of this the Sub-List has been altered to include all hills that have a minimum of 20m of drop but are not known to attain the minimum 30m of drop to enter the main list.

The hills listed below are those major amendments to the original Welsh 200m P30 list as it appears on Geoff’s website.  There are many hills that have been promoted from the Hills to Survey Sub-List to the main list, whilst there are many additions to the Sub-List now that it has been standardised to include all 20m minimum but below 30m drop hills.

When the 200m P30 list was first published it was the first to this category of hills and in some way it and its other 100m height band lists paved the way for Clem’s data that later appeared on the RHB file database and then for the TuMPs listing by Mark Jackson.

As well as the first P30 list to this height band the list is now the first to include a comprehensive Sub-List.

TuMP baggers beware; as the main list also includes P30’s not listed by Mark Jackson, so if you want to visit all P30’s you’ll have to include some non TuMPs to do so.

The list will be updated on a weekly basis and will be done so through each Group category, starting from the north and working south.  The eleventh Group is Carnedd Wen.



Carnedd Wen 
North and west of the Afon Hafren (River Severn) and the border with England at SJ 328 158 to SO 027 916, continuing north of the Afon Carno to bwlch at SN 930 998, and north of the Afon Laen to SH 896 025, continuing east of the Afon Rhiwsaeson and the Nant Carfan to bwlch at SH 891 083, and continuing east of the Afon Tafalog to SH 890 121, continuing south of the Afon Dugoed to Bwlch y Fedwen at SH 934 138 and the Afon Banwy to SJ 143 114, continuing south of the Afon Efyrnwy (River Vyrnwy) to the border with England at SJ 268 205.  Bordering with Y Berwyn to the north, Mynydd y Cemaes to the west, Pumlumon, Pegwn Mawr and Beacon Hill to the south and Cefn Digoll, Breiddin and the English border to the east.    



Twmpau - 200m updates

Bwlch Clump    262m    SJ 170 108

This is a new twin top with an already existing Welsh 200 P30 hill.  The name of Bwlch Clump is taken from the Ordnance Survey enlarged Geograph map, as indeed is the 262m summit height.  The existing P30 that this is twinned with is Pt. 262m (originally listed by the part invented name of Pen y Bryn Wood) which is positioned at SJ 173 109.


Stingwern Wood    c 258m    SJ 145 000

This is a summit relocation from Pt. 251m (originally listed by the part invented name of Pen Cefnblewog) which is positioned at SO 154 996.  The original listing prioritised the 251m spot height position on the OS 1:25,000 Explorer map in preference to a c 250m contour ring, even if the contour ring at SJ 145 000 was large in comparison to where the spot height contour ring appears at SO 154 996.  The new summit position has an uppermost c 255m contour ring on the OS enlarged Geograph map, to complicate matters there is another separate c 255m contour ring at SO 147 994 at Upper House Wood, the former is prioritised as the c 255m contour ring is larger.  No absolute height has been found on any Ordnance Survey map for the new summit location.


Boncyn y Beddau    253m    SO 107 981

This is a promotion from the Sub-List and a new p30 that doesn’t appear in Mark Jackson’s list of the TuMPs.  The hill was originally listed as Bryn y Brain, a part invented name from the wood to the south of the summit.  The critical area for this hill’s inclusion to the P30 ranks is its bwlch.  The contouring on most current Ordnance Survey maps is between c 220m – c 230m.  However, the enlarged Geograph map has 5m contour intervals and narrows the margin of interpolation down to c 220m – c 225m.  This latter map has the hill to hill contours very close together and centred on a road near to a junction with a track at SO 10782 98745, implying a c 224m bwlch, with c 29m of drop.  This is beside a house named as Bryn View on old maps.  The opposing valley to valley contours are relatively far apart, with a 222m spot height appearing at SO 10965 98831 on the enlarged Geograph map.  This spot height is near to a pool that does not appear on any other OS map, this pool is situated where an old clay pit is positioned on old maps.  The 5m interval Geograph hill to hill contours seem to dismiss this 222m spot height as being positioned too low for the critical bwlch.  But all other OS maps (including the Seventh Series, New Popular and Historical 1:25,000) indicate the critical bwlch to be centred near to where the 222m spot height appears on the current enlarged Geograph map.  Driving around these lanes in a Google Car also substantiates the position of the 222m spot height as a more favourable critical bwlch position when compared to the road immediately beside the house named as Bryn View on old maps.  Google Cars are not the be all and end all for critical bwlch positions, but they are good fun!  Hedges and tree growth in this area are quite high but a view can be found that follows the valley to valley traverse from beside Bryn View past another house toward the old clay pit.  This view suggests that the ground is still rising from the 5m contour interval centred position on the road at SO 10782 98745 to the position where the 222m spot height appears on the map.  Therefore, the 222m spot height is being taken as the position for the critical bwlch, giving this hill 31m of drop.


Pt. 249m    249m    SO 137 950

This is a promotion from the Sub-List.  This hill was originally listed by the name of Bryn-rorin, as this is the name of a farm to the north-east of the summit the Pt. notation is being used.  The old 241m height of the hill was taken from the Ordnance Survey 1:50,000 Landranger map with the spot height appearing at SO 13866 95066.  With the advent of the enlarged map on the Geograph website many more spot heights are now available, including a 249m spot height at SO 13701 95036 for this hill.  The bwlch is positioned in one of two spots; 213m at SO 139 957 or c 213m at SO 144 957, giving this hill a drop of 36m / c 36m.


Pt. 238m    238m    SO 111 962 / SO 103 962

This is another promotion from the Sub-List.  This hill was originally listed as a twin summit with c 230m tops, one listed as Bryncoch and the other listed as Bryneithin.  As each name applies to a near farm the hill is now listed under the Pt. notation.  Although the names have been dispensed with the twin top status remains, as each summit is given a 238m spot height on the Ordnance Survey enlarged Geograph map.  The bwlch contouring is between c 205m – c 210c and is estimated as c 208m and centred at SO 102 964.  The 207m spot height near to this centralised position is considered too low and not at the critical bwlch.  The 238m summit and c 208m bwlch value give this hill c 30m of drop.



Sub-Twmpau - 200m updates

Pt. 289m    289m    SJ 080 032

A new hill for the Sub-List as it has a 289m summit spot height and a 261m bwlch spot height at SJ 076 032, which is on a minor road adjacent to the farm of Llawnt Isaf.  These values give this hill 28m of drop.


Pt. 299m    299m    SJ 173 073

Another new hill for the Sub-List and another hill that follows the Pt. notation as no suitable name is known for the hill by the blog author.  The hill is positioned on the Welshpool Golf Course, close to where I live.  Its immediate parent hill is the Marilyn of Y Golfa (SJ 182 070).  With a summit spot height of 299m and a bwlch spot height of 272m at SJ 174 071, this hill has 27m of drop.   


Pt. 269m    269m    SJ 061 016

A hill that is positioned just to the north of a farm named Llwyncopa.  It has a 243m bwlch spot height at SJ 065 016 and a 269m spot height at the summit.  The latter appearing on the Ordnance Survey enlarged Geograph map.  These values give this hill 26m of drop.


Pt. 268m    268m    SH 996 069

As no appropriate name is known by the blog author for this hill, it follows the Pt. notation (yet another one – there’s a lot of research required to find appropriate names for these Welsh 200m Sub-P30 hills).  The Ordnance Survey enlarged Geograph map has a 268m spot height on the area of the summit, the bwlch contouring is between c 240m – c 250m, with the height of the critical bwlch being estimated as c 242m, giving this hill c 26m of drop.


Pt. 278m    278m    SJ 114 004

This hill that is neatly positioned between the farms of Cefngwernfa to its south-west and Bryncaemaeshir to its east.  The summit has a 278m spot height and as the Ordnance Survey enlarged map on the Geograph website has contours at 5m intervals, it narrows the bwlch height to between c 250m – c 255m, with the height estimated as c 253m.  These values give the hill c 25m of drop.


Pt. 247m    247m    SJ 186 126

This hill has a 247m spot height on the Ordnance Survey 1:50,000 and 1:25,000 map that is adjacent to a triangulation pillar that has a 245m map height.  The trig is named Cae-Bardd (Caebardd is a farm north-eastward of the summit) and is given a flush bracket height of 245.668m in the OS Trig Database.  The base of the trig will be approximately 30cm lower than the flush bracket height – 245.37m.  This height is still 1.6m lower than the 247m spot height; therefore there should be ground significantly higher on this hill when compared to the trig position.  I’ve looked on the excellent TrigpointUK.com website and there are 13 photos showing the trig, many are quite close, but those that show ground away from the trig do not show any that is higher.  However, one photo does show a bench, so for those visiting this hill you can relax and admire the view whilst contemplating where the higher ground is.  The bwlch contouring is between c 220m – c 230m and has been estimated as c 222m, giving this hill c 25m of drop to the spot height of 247m.


Pen y Garreg    219m    SO 161 960

This hill (map composition of Pen-y-gareg) has a 219m summit spot height on the Ordnance Survey enlarged Geograph map and bwlch contours between c 190m – c 195m, with an estimated bwlch height of c 194m, giving this hill c 25m of drop.


Pt. c 256m    c 256m    SO 092 962

Both the summit and bwlch height have been estimated from contour interpolation, with the Ordnance Survey enlarged Geograph map having 5m contour intervals.  The summit has an uppermost c 255m contour ring with the height estimated as c 256m, whilst the bwlch contouring is between c 230m – c 235m with an estimated bwlch height of c 232m, giving this hill c 24m of drop.


Pt. 217m    217m    SO 164 995

Another hill that benefits from the Ordnance Survey enlarged Geograph map having contour intervals at 5m.  The summit has a 217m spot height and the bwlch contours are between c 190m – c 195m with an estimated bwlch height of c 193m at SO 159 996, giving this hill c 24m of drop.


Pt. 259m    259m    SJ 104 024

With a bwlch spot height of 236m at SJ 104 028 on the Ordnance Survey enlarged Geograph map, this hill has a drop of 23m. 


Pt. 289m    289m    SJ 106 031

The hill is listed under the Pt. notation, although there is a farm named Maesprydd which is adjacent to the 289m spot height.  The area of the bwlch has a 267m spot height on the Ordnance Survey enlarged Geograph map, but it’s position is judged to be too high  on the hill to hill traverse.  Therefore the height of the bwlch is estimated to be c 266m from contouring between c 265m – c 270m, giving this hill c 23m of drop.


Pt. 247m, Moel y Garth    247m    SJ 203 097

The Ordnance Survey enlarged Geograph map has a 247m summit spot height for this hill and with an estimated bwlch height of c 224m (bwlch contouring between c 220m – c 225m) it gives this hill c 23m of drop.


Pt. 247m    247m    SJ 069 007

Another hill’s estimated drop that benefits from the Ordnance Survey enlarged Geograph map having contour intervals at 5m.  The bwlch contouring is between c 220m – c 225c and has been estimated as c 224m at SJ 067 009, giving this hill c 23m of drop.


Pt. 299m    299m    SJ 071 043

The 299m summit spot height appears next to what may be a cow shed attached to a farm named Bryngwewir.  This name may also apply to the hill, but until further enquiry can be made the name follows the Pt. notation.  The bwlch contouring is between c 275m – c 280m, with the bwlch height being estimated as c 277m, giving this hill c 22m of drop.


Pt. c 296m    c 296m    SJ 108 050

A hill whose summit and bwlch height have been estimated from contour interpolation, but as the Ordnance Survey enlarged Geograph map has contour intervals at 5m it makes the task a little easier.  The summit has an uppermost c 295m contour ring and has been estimated as c 296m, whilst the bwlch contouring is between c 270m – c 275m and has been estimated as c 274m at SJ 109 049, giving this hill c 22m of drop.


Pt. c 275m    c 275m    SO 079 960

The Ordnance Survey enlarged Geograph map has a small uppermost c 275m contour ring at the summit (estimated as c 275m high) and a bwlch spot height of 253m at SO 079 958 which gives this hill c 22m of drop.


Pt. 259m    259m    SO 087 963

The bwlch has a 238m spot height at SO 083 961 on the Ordnance Survey enlarged Geograph map, this could easily be positioned at the critical bwlch, but the valley to valley contours are closer to one another and centred on a bwlch position at SO 085 961.  Therefore the height of the bwlch has been estimated as c 237m at SO 085 961, giving this hill a drop of c 22m.


Pt. c 206m    c 206m    SJ 167 061

The summit has been estimated as c 206m from an uppermost c 205m continuous ring contour and the height of the bwlch has been estimated as c 184m, from bwlch contouring between c 180m – c 185m, giving this hill c 22m of drop.  This is another hill that follows the Pt. notation as no appropriate name is known for it by the blog author.


Pt. 268m     268m    SJ 166 120

The summit has a 268m spot height on it that appears on the 1:25,000 and Geograph map, whilst the bwlch has a 247m spot height that comes from the Ordnance Survey enlarged Geograph map, giving this hill 21m of drop.


Pt. 279m     279m    SJ 013 079

There are two possibilities for the position of this hill’s critical bwlch.  The first is at SJ 010 082, and the second is at SJ 011 084, both have contouring between c 255m – c 260m, and both have been estimated as c 258m.  With a summit height of 279m, this gives the hill c 21m of drop.


Pt. c 245m     c 245m    SJ 084 023

Contour interpolation is helped by the Ordnance Survey enlarged Geograph map having 5m contour intervals.  The summit has a small c 245m uppermost contour (estimated height of c 245m, it is quite small!) and the bwlch contouring is between c 220m – c 225m, with an estimated height of c 224m at SJ 083 026.  These values give this hill c 21m of drop.


Pt. 243m     243m    SO 159 963

Another hill that follows the Pt. notation as the blog author does not know an appropriate name for the hill.  Bwlch contouring is between c 220m – c 225m, with an estimated height of c 222m, giving this hill c 21m of drop.


Pt. 238m     238m    SO 099 969

The Ordnance Survey enlarged Geograph map has a 238m summit spot height for this hill, it also gives a 236m height to a mound south-eastward of the summit.  The bwlch contouring is between c 215m – c 220m and has been estimated as c 217m, giving this hill a drop of c 21m.


Pt. 207m     207m    SJ 041 097

The bwlch contouring for this hill is between c 185m – c 190m and has been estimated as c 186m, giving this hill c 21m of drop.



Pt. 229m     229m    SJ 193 097

The summit and bwlch are both spot heighted on the Ordnance Survey enlarged Geograph map with 229m and 209m (SJ 184 096) respectively, these values give this hill 20m of drop.  The enlarged Geograph map also spot heights another summit contender as 227m at SJ 191 095.


Pt. 214m     214m    SO 120 974

The area of the bwlch has a 194m spot height on it on the Ordnance Survey enlarged Geograph map at SO 122 975.  This value gives the hill 20m of drop.


Pt. 282m     282m    SH 997 098

This hill’s bwlch contouring is between c 260m – c 270m and has been estimated as c 262m, giving the hill c 20m of drop.  This is another example where the Pt. notation is used for the name of the hill as no appropriate name is known by the blog author.


Pt. c 252m     c 252m    SO 110 935

Although both summit and bwlch height have been estimated from contour interpolation, the hill benefits from having contour intervals at 5m on the Ordnance Survey enlarged Geograph map.  These are c 250m for the summit (estimated as c 252m) and c 230m – c 235m for the bwlch (estimated as c 232m).  These values give this hill c 20m of drop.


Pt. 249m     249m    SJ 012 092

The summit has a 249m spot height on the Ordnance Survey enlarged Geograph map, the bwlch contouring is between c 225m – c 230m and is estimated as c 229m, giving this hill c 20m of drop.


Pt. c 216m     c 216m    SO 120 987

The summit height has been estimated as c 216m from an uppermost contour of c 215m, whilst the bwlch has a 196m spot height on it on the Ordnance Survey enlarged Geograph map, giving this hill c 20m of drop.


Pt. 204m     204m    SJ 140 092

The summit height for this hill is unusual as the Ordnance Survey enlarged Geograph map has contour intervals at 5m, and has an uppermost contour of c 205m that has a 204m spot height in it, whilst the ground between the c 200m – c 205m contours has a 205m spot height in it.  I’ve opted for caution and decided to list the hill with a summit height of 204m.  By doing so it means this hill has a twin 204m top at SJ 142 089.  The bwlch contouring is between c 180m – c 185m and is estimated as c 184m.  There is a 182m spot height at SJ 142 096 on the area of the bwlch on the enlarged Geograph map; this is considered too low and not positioned at the critical bwlch.  The hill is listed with c 20m of drop.


Next update due on the 30th June 2014

Sunday, 22 June 2014

Mapping Mountains – Trimble Surveys – Y Berwyn


21.06.14  Mynydd Tarw (SJ 112 324), Pt. 687.9m (SJ 102 330), Foel Wen (SJ 099 334), Tomle (SJ 085 335), Cadair Fronwen (SJ 077 346), Craig Berwyn (SJ 071 323), Moel Sych (SJ 066 318), Pt. 694.7m (SJ 080 317) and Godor (SJ 094 307).

The high Berwyn, (L-R) Moel Sych, Craig Berwyn and Cadair Berwyn
Living in Welshpool the nearest ‘big’ walk for me is the Maen Gwynedd Horseshoe.  I’ve done this walk many times, with past and present hill walking friends as well as on numerous occasions by myself.  I’ve also surveyed some of the small prominence hills on the horseshoe with my old staff for possible P15 status, but I’ve never set out with the intention of surveying all eleven hills and ten bylchau that take in the whole horseshoe. 

The main advantages of using the Trimble is its internal antenna which enables accurate results to be attained with the use of one piece of equipment which weighs just 2lb, and staggeringly these accurate results can be attained with just two minutes of data collection, I knew from past experience that when planned survey points exceed ten the time on the hill dramatically increases, as even though the minimum of data I collect is five minutes it takes quite some time to walk the surrounds of a bwlch and determine its most likely position.  With this in mind I wanted to visit the eleven hills above Cwm Maen Gwynedd on a day that had long daylight hours and with the weather forecast set fine and dry.  Today was the day as it was the 21st June and the forecast was for dry weather, with fair weather cloud in the afternoon and a slight northern breeze which would dampen the heat of the day.

As I drove toward Llanfyllin the high Berwyn were in cloud, this extended out from the west and north like a roughly rolled piece of dough.  I parked at SJ 118 306 where a couple of cars can easily be pulled off the road next to a small bridge that crosses the Afon Iwrch (roebuck river), a name that conjures times when the land was different to nowadays.

I’d brought all manner of surveying implements with me, including a pole, clamp, steel tape, two Tupperware boxes, draughts board, dog lead and of course the Trimble.  I imagined I may need them all, thankfully I didn’t use the Tupperware, draughts board or the dog lead, all of which may have caused a few eyebrows to be raised by any passing hill walker.

Except for the occasional bark of a farm dog and the gentle flapping of overnight washing hanging out to dry, the countryside was quiet as I set off walking at 7.50am.  The route to the first hill of the day; Mynydd Tarw, goes through two farm yards before access to the hill can be gained. 

Passing through one of the farm yards on the way up to Mynydd Tarw
The distinct triangular wedge of forestry on the south-eastern side of Mynydd Tarw has now been cut on its lower section, leaving the customary assault course of tree stump and rutted land.  As I gained height the remnants of early morning cloud was pushed across the sky by a strong north wind.  I was sheltered from this approaching from the south but once on the summit I had to put my summer one skin jacket and thin gloves on as hanging around waiting for surveying equipment to gather data can sometimes be a chilly business.

At the summit of Mynydd Tarw I had a good look around the base of the ancient Bronze Age summit cairn which has now been fashioned to incorporate a wind shelter and prodded a number of rocks, all moved, I then contemplated placing the Trimble next to a high wooden pole across the fence close to the forestry but as I was trying to establish the highest permanent land I decided upon the inside of the wind shelter.  This wasn’t ideal for the Trimble as it was now inside a walled canyon of rock so the results will be interesting, as a safeguard I also gathered data from one of the upper rocks of the wind shelter and measured the offset with the steel tape to its base.  During data gathering I came across a large furry caterpillar and almost squished it when I forgot about its presence when I clambered over the adjacent fence.

Gathering data at the summit of Mynydd Tarw (SJ 112 324)

A big furry caterpillar
The continuation of the walk follows the ridge fence in a north-western direction on a peaty path amongst heather.  This path can become a quagmire during winter time; today it was almost bone dry and effortless, a sheer joy!  The first bwlch of the day proved interesting as I stumbled around in heather trying to make sense of where the valley to valley traverse reached its high point.  Most bylchau are relatively easy to judge where the hill to hill traverse low point is, it’s the valley to valley direction that seems to cause the problem.  Once the set up position for the Trimble was found I gathered five minutes of data and headed up toward the next hill which the Nuttalls list as Foel Wen South Top.  I’m using the Pt. notation for its name until our planned P15 hill list is published, this will incorporate its locally known name and all P15 data that the Trimble produces.

Gathering data at the summit of Pt. 687.9m (SJ 102 330) with (L-R) Moel Sych, Craig Berwyn, Cadair Berwyn, Tomle and Cadair Fronwen in the background
The summits and bylchau were now coming in quick succession, as next was another bwlch where the first hill walkers of the day passed me, they were doing the horseshoe and no doubt would complete the walk many hours before me.  Next was the summit of Foel Wen followed by its critical bwlch.

The summit of Foel Wen (SJ 099 334) looking back at Pt. 687.9m and Mynydd Tarw

Foel Wen from the approach towards Tomle
The next part of the walk follows the ridge fence as it ascends over 100m to the summit of Tomle.  I gathered data from two points on the summit area, one on the northern side of the fence close to where the 742m spot height appears on the Ordnance Survey enlarged Geograph map, and the other next to the cairn which is on the southern side of the fence.  As the Trimble gathered its data I stood and looked out toward the high ridge with the profile of Craig Berwyn dominating, away across the upper reaches of the Nant Cwm-llawenog stood my next summit; Cadair Fronwen.  Between me and it was another bwlch.

Gathering data at the first option for the summit of Tomle

Gathering data at the second option for the summit of Tomle
Bwlch Maen Gwynedd is situated between Tomle and the main Berwyn ridge and is part of an ancient route that has probably been in existent for millennia, it now has a metal gate on it which the Trimble didn’t like as its first placement was so close to it that the required 0.1m accuracy before the time when data can be logged could not be attained, I replaced it and waited, once achieved I pressed ‘Log’ and ran away as quickly as possible as I didn’t want to obstruct any satellite signals.  Just on the west of the bwlch is an old standing stone, marked as a Boundary Stone on maps, it lay on the ground for many years but with assistance from local farmers it is now embedded back in its rightful place overlooking the bwlch.

Gathering data at the critical bwlch of Tomle

The old boundary stone just above the bwlch with Cadair Fronwen in the background
My route now headed toward the bwlch which is the low point between Cadair Fronwen and the higher Berwyn.  Another metal gate gave access to the land on the west of the fence, I examined the bwlch for quite some time as the continuation of the route toward the top of Cadair Fronwen has railway sleepers on part of it to encourage walkers to keep off the eroded quagmire of bog.  These railway sleepers also cross the bwlch, I thought the task of finding the bwlch position would be easy but a narrow grass gully also crossed the track just to the south of the gate.  It was the high point of this grass gully that I chose and once five minutes of data had been collected I headed up to the summit of Cadair Fronwen.

Gathering data at the critical bwlch of Cadair Fronwen
Another fine and ancient cairn is placed on the high point of Cadair Fronwen, this was once rounded, and unfortunately one side has now collapsed giving a sprawling appearance, but still a marvellous place for our Bronze Age descendants to erect such a monument.  I found land just on its northern periphery to be the highest.

At the summit of Cadair Fronwen (SJ 077 346)
I retraced my steps to the bwlch and headed up toward the main Berwyn ridge.  I’d now been out for over six hours and surveyed five hills, I estimated that the walk with its accompanying surveys may take twelve hours which would mean getting back to the car for 8.00pm, giving two hours leeway as darkness would overtake me at 10.00pm.  However, I was reassured as once high on the ridge the next three summits and two bylchau came quick and fast.

Approaching Cadair Berwyn
Cadair Berwyn is marked with a trig pillar and a map height of 827m (826.922m to the flush bracket in the OS Trig Database), it has the same metric map height as one of its neighbours; Moel Sych.  Old imperial maps used to show Cadair Berwyn as 2712ft and Moel Sych as 2713ft, these same imperial maps never recognised that the peak in between; Craig Berwyn, was in fact higher.  I hoped that today would give a good data set for each hill, one that could be compared to the old imperial heights and confirm which out of Cadair Berwyn and Moel Sych in the higher.

As the Trimble gathered data next to the trig I sat beside a fence stile and ate a sandwich, resting in beautiful surroundings where sky and earth meet and the sound of sky lark song as accompaniment.

Gathering data beside the trig on the summit of Cadair Berwyn (SJ 071 323)
The bwlch between Cadair Berwyn and Craig Berwyn has an elongated pond on it, the Ordnance Survey have chosen the eastern side of this pond to place their 808m spot height.  I found the eastern side of the pond to probably be the outflow, as conditions were dry no water was escaping the pond today, but the land on the eastern side led down from the peaty remnants of the pool.  On the western side of the pool is the continuation of the ridge fence, positioned away from the drop over the cliff edge.  The murky water ebbed up to the fence but land on the opposite side was just a bit higher, signifying that the critical bwlch lay to the west of the pond and not at its east.

At the start of the walk I had decided to gather five minutes of data from each summit and bwlch, this has become customary for bwlch placement, but I normally gather ten minutes of data from each summit.  But with over twenty data sets to take during the walk I had decided to restrict the amount of data from each summit, otherwise I may become a surveying benightment, forever lost in a Berwyn bog.  However, I had all intention of collecting at least ten minutes from the next summit as no accurate absolute height has ever been given to the high point of Y Berwyn.

The high point of Y Berwyn; Craig Berwyn was only recognised as such in the late 1980’s.  This is when I took up hill walking and I remember reading an article about Bernard Wright, a former motor oils scientist from Tarvin, Cheshire, who realised that the central peak on the main Berwyn ridge was higher that its two near neighbours; Moel Sych and Cadair Berwyn.  His accompanying friends suggested that the ‘new’ top should be named Craig Uchaf.  I remember reading this with a certain amount of excitement as the Berwyn is an extensive hill range and it seemed incredible that their highest point had only now been recognised, let alone that it did not have a name.  This however, was years before I had contact with local farmers and shepherds, people who have an intricate knowledge of the land that they work.  It seems that our world of hill bagging is somewhat insular and rather neglects local knowledge as the mountain has been thought of as the highest in Y Berwyn for decades and its name also known by local people.

As I approached the highest point where rock formations jut up out of the ground I wanted a few quiet moments to pay respect to my father, as it was from this point that some of his ashes were scattered, overlooking the land he knew as home.  When I reached the highest rock and looked over the edge there were two people sitting just below, I had a quick think about my Dad and started nattering away with them.  I explained about the Trimble and asked if they would be good enough to try and stay below it during data collection, this was no problem as they were happy enough where they were for a good while yet.

Although I’d visited this summit over 30 times I had no memory of the exact formation of the highest rock, I knew you could stand on it, but also knew when doing so you could easily over balance.  But was the very highest rock pointed, flat, or was it tapering?  I’d brought the infamous dog lead so I could attach it to the hand strap of the Trimble when it was gathering data, as if it then toppled off the rock I could save it from falling a few hundred feet over the edge.  The high point proved ideal for Trimble placement and with only a light breeze I judged that the dog lead was not necessary.  However, I did ask the two women if they saw it falling past them could they be good enough to grab it!  As it gathered its ten minutes of data I busied myself with more chat and a number of photos.

The Trimble GeoXH 6000 gathering data at the summit of Craig Berwyn (SJ 071 323), a summit whose accurate absolute height had intrigued me for a number of years

The Trimble perched on the very highest point of Y Berwyn

Safely nestled on the high point of Y Berwyn the Trimble gathers its ten minutes of data
Once ten minutes of data were safely stored we said our farewells and I sauntered off in the sunshine toward the bwlch between Craig Berwyn and Moel Sych.  This proved a problem and it was only at the fourth attempt that the Trimble attained its required 0.1m accuracy.  I eventually decided to attach the Trimble to its pole, but not with its external antenna.  I pushed the pole in to the ground, attached its clamp and the accompanying Trimble and waited for the accuracy to be attained before pressing ‘Log’.  This was the first time I’ve set the Trimble up like this so the result will be interesting, I measured the offset from internal antenna to the ground as 0.87m, this will be taken off the result after post processing.

Llyn Lluncaws below the eastern face of Moel Sych

The critical bwlch of Moel Sych, with Craig Berwyn in the background

The Trimble GeoXH 6000 attached to its pole gathering data
The next summit was Moel Sych where its  ancient summit cairn has undergone the indignity of being re-built as a half wind shelter, where only room for a couple of people sheltering from an eastern wind is possible.  Shame we can’t leave things such as ancient cairns alone without tampering with their appearance.  I checked on surrounding rocks and any that moved when prodded where dismissed for Trimble placement, I found the highest that didn’t and collected another five minutes of data.  All that remained were the three hills on the descending ridge.

Gathering data at the summit of Moel Sych (SJ 066 318)
I backtracked toward Craig Berwyn and followed the narrow path down toward the 698m map height summit of Moel yr Ewig, a name inappropriately used for the 695m map height hill to its east by many hill list compilers.  Just beyond the summit of Moel yr Ewig is the critical bwlch for the qualifying 2,000ft hill.  I lay in the heather as the Trimble gathered data and enjoyed the sun, safe in the knowledge that the surveying expedition would be completed before night fall.

I gathered data from two points at the 695m map height hill that the Nuttalls and Alan Dawson list as Moel yr Ewig.  Again I sprawled out in the heather enjoying the rest and looking out over Cwn Maen Gwynedd toward the hills I’d visited earlier in the day as the Trimble lay in the grass, bilberry and heather quietly gathering its all important data.

Looking south-eastward from one of the high points of Pt. 694.7m (SJ 080 317)

Looking north-westward from one of the high points of Pt. 694.7m (SJ 080 317)
Next stop was a bwlch that proved to be the most difficult of the day, this did not surprise me as I knew the land hereabouts but I had never gone off piste before, having always kept to the path that makes its way through the morass of heather and bog.  Once amongst the peat groughs and drainage channels I tried to evaluate the critical bwlch position to the best of my capabilities, it reminded me of a smaller version of the Meall Cala bealach that John, Graham, Alan and I had surveyed in July 2009.  As the Trimble gathered its five minutes of data I lay in the heather quite close to it as it was impersonating the proverbial needle in a haystack.

Just three surveys remained and the majority of fair weather cloud had dispersed, leaving a radiant early evening blue sky with pleasant giving warmth.  Soon data from the hill the Nuttalls list as Godor North Top had been gathered and I made my way down toward the last bwlch of the day.  I found a small land bridge that bisected two stagnant small bogs, placed the Trimble on some wet grass and settled down in the heather for my customary five minutes of laziness as it chugged away doing its stuff.  Just one hill to go!

Looking back at the high Berwyn from the summit of Pt. 675m (SJ 089 311)
The summit of Godor is crowned by a small quartz rock cairn with the high point of the hill just beside it.  As the Trimble received signals from orbiting satellites I soaked up the early evening’s light and thanked the hills for a marvellous day.  One I probably will never repeat on these particular hills, but a day that took me away from the ease of the path in to the heather bound confines of bwlch, and one that gave me a greater appreciation of these hills and the land that they are a part of.

Gathering data at the summit of Godor (SJ 094 307)
As the sun sank lower in the western horizon I contentedly made my way down in to Cwm Maen Gwynedd through fields of Buttercups and breeze blown swaying grass, with long shadows cast as the glow of evening light on adjacent hills illuminated the land.

Delicate evening light on grasses

Merging yellows with greens

Breeze blown swaying grasses

The ridge from Mynydd Tarw to Cadair Fronwen bathed in evening light

The path home

Shadows on a leaf

Looking back towards Godor as the sun sinks ever lower
The day’s totals proved a record for my Trimbe surveys with eleven summits and ten bylchau surveyed, and in all 25 data sets taken.  I arrived back at the car at 8.30pm, the surveying expedition having taken 12 hours 40 minutes.



Survey Result:

Mynydd Tarw

Summit Height:  679.4m (converted to OSGM15)

Summit Grid Reference:  SJ 11265 32439

Bwlch Height:  635.2m (converted to OSGM15)

Bwlch Grid Reference:  SJ 10755 32695

Drop:  44.2m

Dominance:  6.50% 




Pt. 687.9m (based on later Leica GS15 survey)

Summit Height:  688.1m (converted to OSGM15)

Summit Grid Reference:  SJ 10237 33045

Bwlch Height:  666.4m (converted to OSGM15)

Bwlch Grid Reference:  SJ 10100 33264

Drop:  21.7m  (Subsimm, Sub-Hewitt and 600m Sub-Twmpau status confirmed)

Dominance:  3.13% (based on later Leica GS15 summit survey and Trimble GeoXH 6000 bwlch survey)




Foel Wen

Summit Height:  690.5m (converted to OSGM15)

Summit Grid Reference:  SJ 09970 33400

Bwlch Height:  631.7m (converted to OSGM15)

Bwlch Grid Reference:  SJ 09387 33625

Drop:  58.8m

Dominance:  8.54% (based on later Leica GS15 summit survey and Trimble GeoXH 6000 bwlch survey)




Tomle

Summit Height:  740.7m (converted to OSGM15)

Summit Grid Reference:  SJ 08529 33529

Bwlch Height:  719.8m (converted to OSGM15) 

Bwlch Grid Reference:  SJ 08087 33716

Drop:  20.9m (Sub-Simm, Sub-Hewitt and 700m Sub-Twmpau status confirmed)

Dominance:  2.82% 




Cadair Fronwen

Summit Height:  783.4m (converted to OSGM15)

Summit Grid Reference:  SJ 07754 34661

Bwlch Height:  710.1m (converted to OSGM15)

Bwlch Grid Reference:  SJ 07602 34085

Drop:  73.3m 

Dominance:  9.35%





Summit Height:  832.0m (converted to OSGM15)

Summit Grid Reference:  SJ 07163 32351

Drop:  c 346m

Dominance:  41.59%




Moel Sych

Summit Height:  826.7m (converted to OSGM15)

Summit Grid Reference:  SJ 06627 31858

Bwlch Height:  792.8m (converted to OSGM15)

Bwlch Grid Reference:  SJ 06944 32140

Drop:  33.9m  (Simm, Hewitt and 800m Twmpau status confirmed)

Dominance:  4.11%




Pt. 694.7m

Summit Height:  694.7m (converted to OSGM15)

Summit Grid Reference:  SJ 08073 31773

Bwlch Height:  670.6m (converted to OSGM15) 
                   
Bwlch Grid Reference:  SJ 07743 31823

Drop:  24.2m  (Sub-Simm, Sub-Hewitt and 600m Sub-Twmpau status confirmed)

Dominance:  3.48% 




Godor

Summit Height:  679.2m (converted to OSGM15)

Summit Grid Reference:  SJ 09431 30747

Bwlch Height:  654.3m (converted to OSGM15) 
                   
Bwlch Grid Reference:  SJ 09082 31013

Drop:  24.9m  (Sub-Simm, Sub-Hewitt and 600m Sub-Twmpau status confirmed)

Dominance:  3.67% 



For details on the second survey of Foel Wen and Pt. 687.9m

For further details please consult the Trimble survey spreadsheet click {here}