Mapping Mountains – Hill Reclassifications – Humps

Foel Grafiau (SN 765 920) – Non-prioritised Twin Hump deletion

This is the twenty fifth in a series of Hill Reclassification posts that detail hills whose status has been altered in the listing of the Humps (HUndred Metre Prominences) through map study and / or surveys that I have instigated.

The hill that was listed as Foel Grafiau in the Humps and still is in the Tumps (SN 765 920)

The hill name used in this and forthcoming posts is that used in the listing of Humps, therefore individual names and their composition may not match those that are used in listings I am directly associated with.  However, I am of firm belief that listed hill names used by other authors should be respected when giving detail within other people’s lists, however inappropriate some hill names may be considered.

This and forthcoming posts are retrospective as many of these hill reclassifications were initiated from studying the Ordnance Survey enlarged mapping that is hosted on the Geograph website, or in this instance from a survey with the Trimble GeoXH 6000, and for the reclassifications that affected the Humps the survey of this hill took place on the 18.05.14.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for the reclassification appear below:

There has been a reclassification to the listing of the Humps (HUndred Metre Prominences) instigated by a survey with the Trimble GeoXH 6000 which took place on the 18.05.14.

Mark Jackson had originally listed this hill with c 30m of drop based on the 529m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 499m based on bwlch contouring at 10m intervals.  This hill was listed as a non-prioritised Twin Hump along with two other 529m summit spot heighted hills which are positioned at SN 764 943 (previously listed as non-prioritised Twin Hump) and SN 765 926 (previously listed as prioritised Twin Hump).  Therefore, prior to the survey with the Trimble GeoXH 6000 this hill was listed as a non-prioritised Twin Hump.

The hill appeared under the name of Foel Grafiau in the listing of the Humps, this is the name of a 493m map heighted hill that is listed as a 400m Sub-Pedwar and which is positioned at SN 959 920.  However, research via the Tithe map confirms the hill that appeared in the Humps by the name of Foel Grafiau and which is still listed in the Tumps as being the highest point on the former sheep-walk of Lluest y Rhos, with the hill listed in the Y Pedwarau as Mynydd Lluest y Rhos (see Significant Name Changes).

The hill is adjoined to the Pumlumon group of hills and is situated between the A 489 road to the north and the A 44 road to the south, and is positioned between the town of Machynlleth towards the north and the small community of Ffwrnais (Furnace) towards the west.

This hill and its adjacent twin map heighted summits were surveyed using a Trimble GeoXH 6000 by Myrddyn Phillips on the 18.05.14 resulting in a 528.3m (converted to OSGM15) summit height, which proved lower than the 529.4m (converted to OSGM15) summit at SN 764 943, with the other summit being 528.7m (converted to OSGM15) at SN 765 926, with this survey confirming this hill’s deletion from non-prioritised Twin Hump status with 30.0m of drop.

The deletion of this hill from non-prioritised Twin Hump status was accepted by Mark Jackson and it was removed from the listing of the Humps on 22.09.14.

Gathering data with the Trimble GeoXH 6000 at the summit positioned at SN 765 920

The full details for the hill are:

Name:  Foel Grafiau (as listed in the Humps)

Summit Height:  528.2m (as listed in the Humps) (528.3m converted to OSGM15)

OS 1:50,000 map:  135

OS 1:25,000 map:  23, 215

Summit Grid Reference:  SN 76546 92035 (as listed in the Humps)

Drop:  30.0m

Myrddyn Phillips (November 2017)

Mapping Mountains – Significant Name Changes – Y Pellennig - The Remotest Hills of Wales, Yr Uchafion and 500m Twmpau

Mynydd Lluest y Rhos (SN 765 920)

There has been a Significant Name Change to a hill that appears in the following listings, Y Pellennig - The Remotest Hills of Wales, Yr Uchafion and the 500m Twmpau, with the following details relating to a hill that was surveyed with the Trimble GeoXH 6000 on the 18^th May 2014.

The criteria for the three listings that this name change affects are:

Y Pellennig –The Remotest Hills of Wales comprise all Welsh hills whose summit is 2.5km or more from the nearest paved public road and which have a minimum 15m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams.

Yr Uchafion - All Welsh hills at or above 500m in height that have 15m minimum drop.  The list is co-authored by Myrddyn Phillips and Aled Williams. 

500m Twmpau - All Welsh hills at or above 500m and below 600m in height with 30m minimum drop.  The list is authored by Myrddyn Phillips.  

The hill is situated in the Pumlumon group of hills, and is relatively remote for a Welsh hill with the nearest towns being Machynlleth towards the north, Tal-y-bont towards the west, Ponterwyd towards the south and Penffordd-las (Staylittle) towards the east.

Mynydd Lluest y Rhos (SN 765 920)

The hill first made an appearance in an unpublished hill list in 1985 when Tony Blackburn listed it as top S Hafodwnog in his The 500 Metre Tops of England and Wales, and it was later included by Michael Dewey as Foel Grafiau in The 500-Metre Tops of England and Wales list that appeared in his Mountain tables book published by Constable in 1995.

Hill list authors are prone to list a hill by the name that appears nearest to its summit on Ordnance Survey maps, without much consideration for its local or historical confirmation, or whether map placement is appropriate.  However, place-name data can be improved by asking local people and examining historical documents and since this hill’s inclusion by Michael Dewey in his 500-Metre Tops list the area where this hill is situated has been examined via a number of documents including the Tithe map.

As a result this hill has subsequently been listed by the name Mynydd Lluest y Rhos in the Y Pellennig – The Remotest Hills of Wales list, with the following explanation appearing in the Notes section of the booklet version of the list:

Name taken from an 1844 tithe map, which confirms this hill as being the highest point on the former sheep-walk of Lluest y Rhos. 

The term Tithe map is generally given to a map of a Welsh or English parish or township and which was prepared after the 1836 Tithe Commutation Act.  This act allowed tithes to be paid in cash rather than goods.  The Tithe maps gave names of owners and occupiers of land in each parish and importantly for place-name research they also included the name of enclosed land.  This enclosed land is usually based on a field system, however not every field is given a name, but many are and especially so in Wales.

The sheep-walk is an English term given to enclosed land that is apportioned to a specific farm.  The Welsh term for this land is cynefin, which can literally be translated as habitat, as in that for the sheep.  The cynefin usually takes in high land that is known as the mountain land of the specific farm, therefore the name given to this enclosed land is usually that of the name of the farm prefixed with the word mynydd, this being the Welsh word for mountain, this land is usually given over for sheep grazing, hence the term sheep-walk.  When Ordnance Survey maps are examined one can find many examples where this form of cynefin naming system exists, with farms situated in valley’s having their name given to high mountain land and prefixed with the word mynydd.

The full details for the hill are:

Group:  Pumlumon

Name:  Mynydd Lluest y Rhos

Previously Listed Name:  Foel Cerrigbrithion

 

Summit Height:  528.3m (converted to OSGM15)

OS 1:50,000 map:  135

Summit Grid Reference:  SN 76543 92029

  

Drop:  30.0m (converted to OSGM15)

For details on the survey of Mynydd Lluest y Rhos

Myrddyn Phillips and Aled Williams (July 2016)

Mapping Mountains – Trimble Surveys – Banc Llechwedd Mawr

18.05.14  Pen y Darren (SN 764 942), Creigiau Bwlch Hyddgen (SN 767 931), Foel Fras (SN 765 926), Foel Uchaf (SN 768 925) and Mynydd Lluest y Rhos (SN 765 920).

Creigiau Bwlch Hyddgen (SN 767 931) and Pen y Darren (SN 764 942)

Pumlumon is often celebrated as the source of the Afon Hafren (River Severn), Afon Gwy (River Wye) and the Rheidol and the highest point in mid Wales.  Its ancient name has connotations relating to its five highest peaks, but the beauty of this massif is to the north of these hills, in the escarpment edges, the heather bound hills to the north of the Afon Hengwn, the forgotten valleys and the solitude of the hills to the north of Nant y Moch Reservoir.  It was some of these latter hills we wanted to investigate today.

The hills to the north of Nant y Moch Reservoir form a chain starting with the isolation of Drosgol (SN 759 878) and Banc Llechwedd-mawr (SN 775 898), before the relative ease of Bryn Moel (SN 772 911), Mynydd Lluest y Rhos (SN 765 920), Foel Uchaf (SN 768 925), Foel Fras (SN 765 925), Creigiau Bwlch Hyddgen (SN 767 931) and Pen y Darren (SN 764 942).  Three of these hills are of particular note as they all have the same 529m map spot height given to their summits.  It was these hills that Mark had suggested we prioritise for today’s survey.  I say prioritise as the origin plan forwarded to Mark was to approach from the south and survey seventeen points, Mark thought this too ambitious and suggested concentrating on the priority hills and approaching from the north.  He also suggested that if time and inclination permitted we may visit the summit of Pen Criegiau’r Llan (SN 745 939) towards the end of the walk.

We parked near to the buildings named Cwmyrhaiadr at SN 756 963, where sufficient space can be found for two or three cars.  This is toward the end of Cwm Rhaiadr, a quiet and beautiful valley south-east of Glaspwll (SN 738 975) and south of the town of Machynlleth.

The day’s forecast was good with sunshine and a light breeze, with the possibility of high cloud pushing in from the west toward late afternoon.  There are at least three options for the ascent route toward Pen y Darren from where we parked, we opted for the one signposted ‘Private’.  This led us up the hill on a good forest track beside the Nant Cwm-cemrhiw before height was gained with a series of zig zags.  I couldn’t help myself as every few minutes I stopped and tried to do the luxuriant flora justice with another photograph.

The ascent through the forest

The track soon brought us out above the near conifer plantation, an incomer amongst the lush canopied deciduous tree growth of the small stream valleys below.  We contoured around the western flank of Pen y Darren on the track before branching up over its upper hillside of bilberry to its three summit domes, these are similar to tumuli in shape and appearance but closer inspection shows natural rock formations jutting out from their sides.  We Trimbled the two highest mounds and lay in the sun relaxing next to tiny alpine plants as a male Emperor Moth darted beside us, a blur of colour, an unexpected and rather impressive visitor to such a place.  Once ten minutes of data was collected from each mound we headed south toward the first bwlch of the day.  This consisted of a large bog, once we decided where we thought the critical bwlch was positioned we set the Trimble and Mark’s hand-held GPS to gather data and retired to the drier confines close to the continuation of the track.

Gathering data on the first summit mound on Pen y Darren

Gathering data on the second summit mound on Pen y Darren

This track would serve us well during the day as although these hills are generally grassy, the bylchau are boggy, and the track made for ease of passage between the points that we wanted to survey.  Our next point was the summit of Creigiau Bwlch Hyddgen, another top consisting of grass and bilberry.

The Trimble GeoXH 6000 collecting data on the summit of Creigiau Bwlch Hyddgen with (L-R) Foel Uchaf, Mynydd Lluest y Rhos and Foel Fras in background

The southern ridge of this hill led us down to the next bwlch, the map indicates there are two possibilities for the position of the critical bwlch, map contouring suggests the first of these can be discounted and so it proved when we arrived at this spot, as the second option was easily seen to be lower.  Again this consisted of a bog, relatively dry due to the sunshine and fine weather of the last week or so, but no doubt a squelchy affair during wet spells.

Foel Uchaf (SN 768 925) from the bwlch between Creigiau Bwlch Hyddgen and Foel Fras

From this bwlch we made our way to the summit of the second of the 529m map height hills; Foel Fras, a central pivot on this ridge, an enlarged bulk and mound of grass, the summit is sponge like and quite flexible when bounced up and down on.  We sat on grass in a convenient peat channel and waited for the customary ten minutes of Trimble data to be gathered, ate a butty and chatted.

Mynydd Lluest y Rhos (SN 765 920) from the summit of Foel Fras

We then headed eastward down the hill toward what proved to be a problematical bwlch, not in the choice of placement for the Trimble, but in the time it took for the equipment to achieve the required 0.1m accuracy before being activated to log data.  The warnings were there from the start as it showed 0.80m when first logged on to a number of satellites and it then spent over 30 minutes creeping down to the magical 0.1m.  This was probably due to the tussock terrain of the bwlch but probably more so with the close proximity of steepness of hill side.  This critical bwlch is just west of the continuation of the track and not east of the track as shown on the Ordnance Survey 1:50, 000 and 1:25,000 maps.  During our prolonged wait we were joined by Adam Lewis who was three or four days in to a 350km off road cycle journey heading south from Conwy to Port Talbot, as we chatted we were joined by Maldwyn Lewis and his canine companions; Mot and Pero, Maldwyn was on a quad bike and was checking a number of gates to make sure that they were closed.  As Maldwyn waved us goodbye as he sped off on his quad bike with Mot and Pero somehow balanced on the back, Adam zoomed off north on the track heading for Nant yr Arian and a quiet spot to pitch his tent.

Adam Lewis on his way from Conwy to Port Talbot

Maldwyn Lewis with Pero and Mot

We spent around 45 minutes waiting for the Trimble to attain its 0.1m accuracy and to gather data

Our next survey was the summit of Foel Uchaf which is positioned directly above the previously surveyed bwlch.  Once data had been collected we headed south toward the next bwlch which proved remarkably easy to find considering the land hereabouts.  Another ten minutes of data was collected whilst we sat in the late afternoon sun.  By now we’d been out over six hours and the prospect of including Pen Creigiau’r Llan at the end of the walk was quickly dismissed.

(L-R) Mynydd Lluest y Rhos (SN 765 920) and Foel Grafiau (SN 759 920) from the summit of Foel Uchaf

Mark heading towards the last bwlch to survey between Foel Uchaf and Mynydd Lluest y Rhos 

Pen Creigiau'r Llan (SN 745 939) would have to wait for another day

Our last summit to survey was Mynydd Lluest y Rhos, a hill to the east of the Sub-Pedwar named Foel Grafiau.  Another convenient grassy seat above layered peat gave us time to relax as the Trimble gathered the all precious summit data.  Mark lay on the summit ridge and looked northward toward the other two 529m map height hills of Pen y Darren and Foel Fras, the two distinct summit mounds of the former could be seen over the slightly lower western summit ridge of the latter.  We both thought that the most aesthetically pleasing hill out of these three 529m map height hills was the one we were on as it has a fine profile when viewed from the direction we walked these hills, but the indication was that Pen y Darren may just be the higher of the three.  Our belly down on the summit ridge and looking out to the other hills approach to surveying was not scientific, but when I tried it I thought the grass smelled rather nice.

Once data had been stored the Trimble was packed away and as Mark quite justifiably observed; we could now go for a hill walk.  After all, surveying many points is not conducive to what most people regard as a hill walk, I do find it fun and it’s great to see the figures appear on the screen during post processing, but surveying does somewhat break the momentum of a walk.

By now the predicted high cloud had milked the sky with the sunshine turning a lazy summered haziness, we descended west over Foel Grafiau and dropped down to a track to the north-west of this hill’s summit.  We followed this as it gained a little height toward the edge of the conifer plantation at the head of Llyn Penrhaeadr.  Just before the conifer plantation we walked out in to a morass of flat bog, relatively dry and becalmed.  Once to the north of the lake we picked up a track and green path that took us to the top of Pistyll y Llyn.

Pistyll y Llyn is one of the tallest waterfalls in Wales and takes the waters of the Afon Llyfnant on a cascading journey from their sedentary passage north of Llyn Penrhaeadr to a downward drop of approximately 160 metres.

Once on the opposing bank of the steam we found the start of the path that descends in to the cwm.  As we started our downward passage we stood and tried to stare over and in to oblivion, problem was that the ground fell away so steeply that we couldn’t see the waterfall from our airy perch, the sound of water was heard and the view was dramatic but the waterfall was completely out of sight until low down in the valley.

Looking down the Afon Llyfnant valley

The path we were now on proved quite dramatic in its upper section as it clings on to the edge of a vertical drop, lower down we lost the main path and walked through copses of fire trees as the sun sank lower in the sky, casting sublime colours on the land.

Evening light followed us down toward the secluded valley at the base of Pistyll y Llyn

Slowly we lost height toward the valley bottom where yellowed reed grass stretched out in a continuous silken bed, green fields with white specks of bleating lambs overlooked by trees heavy with May blossom and the ever present bird song gave an unending quality to the scene, with Pistyll y Llyn as backdrop.

Pistyll y Llyn almost hidden amongst the crags

May Blossom

Pistyll y Llyn at the head of the Afon Llyfnant valley

The last few minutes back to the car were spent walking past the buildings of Cwmyrhaiadr with their golden mature trees and narrow country lanes, a wonderful walk.

Journeys end

Survey Result:

Pen y Darren

Summit Height:  529.4m (converted to OSGM15) (non-prioritised Twin Hump reclassified to Hump)

Summit Grid Reference:  SN 76431 94297

Bwlch Height:  c 426m (interpolation)

Bwlch Grid REference:  SN 77001 90474 (interpolation)

Drop:  c 103m

Dominance:  19.53%

Creigiau Bwlch Hyddgen

Summit Height:  506.1m (converted to OSGM15)

Summit Grid Reference:  SN 76740 93201

Bwlch Height:  482.5m (converted to OSGM15)

Bwlch Grid Reference:  SN 76715 92865

Drop:  23.6m

Dominance:  4.66%

Foel Fras

Summit Height:  528.7m (converted to OSGM15)

Summit Grid Reference:  SN 76544 92604

Bwlch Height:  461.2m (converted to OSGM15)

Bwlch Grid Reference:  SN 76454 93672

Drop:  67.6m (prioritised Twin Hump deletion confirmed)

Dominance:  12.78%

Foel Uchaf

Summit Height:  522.0m (converted to OSGM15)

Summit Grid Reference:  SN 76844 92519

Bwlch Height:  499.1m (converted to OSGM15)

Bwlch Grid Reference:  SN 76808 92229

Drop:  22.9m

Dominance:  4.39%

Mynydd Lluest y Rhos (significant name change)

Summit Height:  528.3m (converted to OSGM15)

Summit Grid Reference:  SN 76543 92029

Bwlch Height:  498.3m (converted to OSGM15)

Bwlch Grid Reference:  SN 76752 92522

Drop:  30.0m (non-prioritised Twin Hump deletion confirmed)

Dominance:  5.68%

As the 30m (30.009m) drop value has an accuracy of + / - 0.1m the result is within the margin of uncertainty of the technology used.  Therefore, it is hoped that a line survey can be conducted to determine the absolute drop for this hill.

For further details please consult the Trimble Survey Spreadsheet click {here}