Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales

Gelli Hir (SN 999 883) – Lesser Dominant addition

There has been an addition to the listing of Y Trechol – The Dominant Hills of Wales with the summit height confirmed by a survey with the Trimble GeoXH 6000 and later substantiated by a survey with the Leica GS15, and the bwlch height later ascertained from LIDAR analysis conducted by Myrccyn Phillips, resulting in this hill being added to the Lesser  Dominant list. 

The criteria for this listing are:

Y Trechol – The Dominant Hills of Wales - Welsh P30s whose prominence equal or exceed half that of their absolute height, with the criteria for Lesser Dominant status being those additional Welsh P30s whose prominence is 33% or more and below 50% of their absolute height.

The details relating to this hill’s addition to the Lesser Dominant list are retrospective as the confirmation was dependent upon a survey with the Trimble GeoXH 6000 which was conducted by Myrddyn Phillips on the 7^th February 2014, the result was later substantiated by a survey with the Leica GS15 which was conducted by John Barnard, Graham Jackson and Myrddyn Phillips on the 2^nd May 2014.

Prior to the survey with the Trimble GeoXH 6000 this hill’s twin 308m map heighted summit of Y Gaer which is positioned at SO 01350 87380 was prioritised as being listed as a Lesser Dominant.  The survey with the Trimble separated these twin map heighted tops and resulted in the deletion of Y Gaer, and the addition of Gelli Hir to Lesser Dominant status.

The name of the hill is Gelli Hir and it is adjoined to the Pumlumon range of hills which are situated in Mid and West Wales (Region B, Sub-Region B2).  The hill has the A 470 road and the Afon Hafren (River Severn) to its east, and is positioned between the small community of Caersws to the north-east and the town of Llanidloes towards the south-west. 

As the summit of the hill is not on designated open access land permission to visit should be sought, however as a public footpath traverses this hill’s elongated and broad summit ridge in a north – south direction and passes close to the high point of the hill, common sense should prevail as a diversion to the summit is only a short distance away.

The addition of Gelli Hir to Lesser Dominant status was confirmed by a survey with the Trimble GeoXH 6000 and then substantiated by a survey with the Leica GS15, resulting in a summit height of 307.2m (converted to OSGM15) which is 0.1m higher than its twin map heighted summit of Y Gaer (SO 013 873), with LIDAR analysis giving the height of the bwlch as 182.5m, resulting in 124.7m of drop and 40.60% dominance this hill is added to the Lesser Dominant list.

The full details for the hill are:

Group:  Pumlumon

Name:  Gelli Hir

Dominance:  40.60% (Leica GS15 summit and LIDAR bwlch)

OS 1:50,000 map:  136

Summit Grid Reference:  SN 99903 88383 (Leica GS15)

Summit Height:  307.2m (converted to OSGM 15, Leica GS15)

Drop Summit to Bwlch:  124.7m (Leica GS15 summit and LIDAR bwlch)

Drop Bwlch to ODN:  182.5m (LIDAR) 

Gelli Hir (SN 999 883) is now added to the ranks of Lesser Dominant hills

For details on the survey that resulted in the addition of this hill to Lesser Dominant status

Myrddyn Phillips (December 2017)

Mapping Mountains – Hill Reclassifications – Humps

Rhos Fawr (SN 999 883) – Subhump reclassified to Hump

This is the twenty first 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 listed as Rhos Fawr in the Humps (SN 999 883)

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 first survey of this hill took place on the 07.02.14.

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 and which was later confirmed by a survey with the Leica GS15.

Prior to the survey with the Trimble GeoXH 6000 Mark Jackson had listed this hill as a Subhump with 91m of drop based on the 308m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and the 217m bwlch spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website.  This hill was listed as a twin as a 308m spot height also appears on Ordnance Survey maps for the hill whose summit is positioned at SO 01352 87384.

The hill appears under the name of Rhos Fawr in the listing of the Humps, this is the name of a farm to the west of the summit and not the name of the hill.  However, local enquiry and research via Ordnance Survey maps and the Tithe map finds that the name of Gelli Hir is more appropriate for this hill (see Significant Name Changes).

The hill is adjoined to the Pumlumon group of hills and is situated with the A 470 road and the Afon Hafren (River Severn) to its east, and is positioned between the small community of Caersws to the north-east and the town of Llanidloes towards the south-west.

This hill and its adjacent twin map heighted summit were surveyed using a Trimble GeoXH 6000 by Myrddyn Phillips on the 07.02.14 resulting in a 124m drop value for this hill, with its adjacent twin map heighted summit being 0.055m lower than Rhos Fawr, the hill was then re-surveyed on the 02.05.14 by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica GS15 and Trimble GeoXH 6000 resulting in the adjacent twin map heighted summit named as Coed Mawr in the listing of the Humps being 0.11m lower than Rhos Fawr, with this survey confirming this hill’s reclassification from Subhump to Hump status.

The reclassification of this hill from Subhump to Hump status was accepted by Mark Jackson and its new classification augmented in to the listing of the Humps on 10.05.14.

Gathering data with the Leica GS15 at the summit of the hill listed as Rhos Fawr in the Humps

The full details for the hill are:

Name:  Rhos Fawr (as listed in the Humps)

Summit Height:  307.2m (converted to OSGM15)

OS 1:50,000 map:  136

OS 1:25,000 map:  214

Summit Grid Reference:  SN 99905 88388 (as listed in the Humps)

Drop:  124m (as listed in the Humps)

Myrddyn Phillips (October 2017)

Mapping Mountains – Significant Name Changes – Y Trichant - The 300m Hills of Wales and Y Trechol - The Dominant Hills of Wales

Gelli Hir (SN 999 883)

There has been a Significant Name Change to a hill that is listed in the Y Trichant and Y Trechol - The Dominant Hills of Wales, with the following details relating to a hill that was surveyed with the Trimble GeoXH 6000 on the 7^th February 2014 and also on the 2^nd May 2014 along with the Leica GS15.

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

Y Trichant - These are the Welsh hills at and above 300m and below 400m in height that have 30m minimum drop,  with the introduction to the re-naming and the publication history of this list appearing on Mapping Mountains on the 13^th May 2017.

Y Trechol - The Dominant Hills of Wales - These are the Welsh P30 hills whose prominence  equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those addition Welsh P30 hills whose prominence is 33% or more and below 50% of their absolute height.

The hill is situated in the Pumlumon range, which is an extensive group of hills in the northern part of mid Wales.  The hill is positioned to the south-west of Caersws and to the north-east of Llanidloes, with the small community of Llandinam and the Afon Hafren (River Severn) to its east.

Gelli Hir (SN 999 883)

The hill appeared in the 300m P30 list on Geoff Crowder’s  v-g.me website under the name of; Rhosfawr, which at that time was taken as the name of the hill, however this is the name of a farm which is situated to the west of the hill’s summit.

Rhosfawr

308m

SN999884

136

214

Clem/Yeaman. Twin top.

The name this hill is now listed by is Gelli Hir, this name can be translated as long grove, and this was derived from examination of the Ordnance Survey Historical 1:25,000 map as well as the Tithe map, coupled with tentative details from local enquiries.  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 Ordnance Survey Historical 1:25,000 map is probably the best OS map for placement of names relating to hills and their features, on this map Gelli Hir appears close to the summit of this hill and following its upper northerly ridge

When I first surveyed this hill I made place-name enquiries with a local resident to the south south-east of the hill.  The details are given below:

After visiting the summit of Y Gaer at SO 013 873, I descended to the farm of Cefn and surprised Graham Pugh who was heading to the farm yard from a large barn full of recently born lambs.  Graham is aged 53 and had lived in the local area for 25 years and at the farm of Cefn for 20 years, he originally comes from Staylittle / Penffordd-las (SN 887 920).  He can speak Welsh but said that he gets his ‘rights’ and ‘lefts’ muddled up and told me about a visit to a market where he was given directions and he couldn’t remember if the word meant left or right, we both chuckled at this.  I believe this was due to a lack of Welsh being spoken in the area where Graham now lives, so his use of the language is not on a daily basis.  I explained where I had come from and where I was heading.  We were soon talking about the name of the hill.

Graham told me he didn’t really know a name for this hill, I asked if he ever referred to the hill by any name and he said that he just calls it Top of the Bwlch.  The farm of Bwlch is situated at SN 995 875, it seems the summit of the hill is on their land.  I asked if he had ever heard the name of Gelli Hir in relation to this hill.  He then said that this was funny as he’d had a recent conversation with the person from Coedmawr farm, who had just bought the land going up to the top of this hill from the other (north-west) side and they had called it Gelli something.  The name of Gelli Hir (Gelli-hir on older maps) appears on current maps just below the summit of this hill.  However, on older OS maps this name appears as a ‘ridge’ name going across the top of the hill and down its northern ridge.

Graham Pugh of Cefn farm

Place-name research can be similar to fitting pieces of a giant jigsaw together, each piece is important, but on occasion the pieces (the information given) seem as if they do not fit together.  However, each piece of information is important and can be assessed against other information found at a later date.  And this was so with this hill’s name, as I already knew that the Historical 1:25,000 map has the name of Gelli Hir following the upper northern ridge of this hill, as this map is by far the most precise produced by the Ordnance Survey for place-name position I was inclined to believe that the name of Gelli Hir was appropriate to use for this hill, and the information given by Graham Pugh, although only tentative, was also substantive when coupled with the placement of this name on the old 1:25,000 map.  I hoped that the Tithe map would substantiate the use of Gelli Hir for this hill’s name.

Unfortunately the Tithe map for this area is almost unintelligible, however the number 2096 is given to the adjoining land to where the summit of this hill is situated, this number can be cross referenced against the apportionments; it is these apportionments that give the name of the owner or occupier of the land as well as the name of the land.  The land given the number of 2096 is named as Allotment on the Tithe map, and importantly the next number; 2097, which is probably the adjoined land, is named as Gelli hir and is described as Pasture; these details are listed under the county named as Montgomery and in the parish of Llandinam.

Accessing information on the Tithe map is simplified by the use of a split screen enabling the summit to be pinpointed on the map on the right and for the same point to appear on the Tithe map on the left.  Unfortunately in this instance the Tithe map is almost unintelligible, however the number 2096 is given to the adjoined land

2096 is named as 'Allotment' with 2097 named as Gelli hir

The full details for the hill are:

Group:  Pumlumon

Name:  Gelli Hir

Previously Listed Name:  Rhosfawr

 

Summit Height:  307.2m (converted to OSGM15, Leica GS15)

OS 1:50,000 map:  136

Summit Grid Reference:  SN 99902 88383 

   

Drop:  124.7m (Leica GS15 summit and LIDAR bwlch)

Dominance:  40.60% (Leica GS15 summit and LIDAR bwlch)

For details on the first survey and the second survey of Gelli Hir

Myrddyn Phillips (June 2016)

Mapping Mountains – Trimble Surveys – Pumlumon

02.05.14  Y Gaer (SO 013 873) and Gelli Hir (SN 999 883)

This is the second of two Trimble surveys of Y Gaer and Gelli Hir, to read the first survey post please click {here}

Gelli Hir (SN 999 883)

These two 308m map heighted hills were Trimbled on the 07.02.14, resulting in a height difference of 0.06m, with Gelli Hir being the higher.  As a 6cm difference is within the margin of uncertainty associated with the equipment the two hill's were prioritised for a Leica GS15 survey.  Currently Mark Jackson has them listed as a twin Hump under the names of Coed Mawr and Rhos Fawr, with Coed Mawr being given priority Hump status and Rhos Fawr listed as the Subhump.

By 9.00am my car had been loaded with all necessary surveying equipment transferred from John's car and along with Graham we made our way toward Llandinam and the minor road between the two hills that follows the Nant yr Hebog.  We scouted around for a suitable parking space and eventually asked permission to park next to a bungalow close to the critical bwlch between the two hills, permission was kindly given, and by 9.50am we were on our way, following the Severn Way up a track and over fields to the northern ridge of Y Gaer and then on to the summit.

There was dullness to the day with high blanketed cloud cover giving a monochrome effect to the land.  The forecast was good with mid Wales predicted to be free of any rain and only a light breeze, which would help as we planned on gathering two hours of data from each hill.

Soon the level and staff was assembled as John looked through the optics and Graham operated the staff.  The summit area of Y Gaer consists of small plateaux like 4m x 4m blob of close cropped grass amongst a greater blob of closely cropped greenery in a sheep grazing field.  Measurements around the summit were within 2cm – 3cm of each other, we soon pinpointed our chosen spot, marked it with a metal stud and put three flags next to it.

As the small summit ridge has a line of trees next to it we levelled away from the high point to where the Leica GS15 set up position was going to be, this was far enough away from the tree coverage not to disrupt satellite signal reception.  Once assembled and switched on we waited for the arrival of Eryl; a good travelling companion and hill walking friend of many a year who planned on joining us for an hour.

Yummy, yummy - quite like the taste of these flags

Stop eating the flags!

Levelling for summit position on Y Gaer

About half an hour later we spotted Eryl making his way up the last section of the northern ridge to join us on the summit; handshakes and hugs proceeded.  I believe the only time Eryl had met John and Graham was on the wake for a deleted Nuttall on the Berwyn ridge, a particularly wet day and an eventful one as we lost Ed for an hour in a lonely mist driven windy land of heather.  He eventually emerged looking rather wild eyed and slightly disheveled.

L-R; Eryl, John and Graham at the Leica GS15 set up position on Y Gaer

Good to see Eryl again, he’d been birding his way up the hill and as John and Graham have a common interest in all things tweety and feathery the conversation flowed.  An hour or so later and he was on his way back down the ridge. 

Once the allotted two hours of data had been gathered with the Leica GS15 and ten minutes of data with the Trimble GeoXH 6000 we packed up the equipment and headed down the southerly ridge to the farm of Cefn (SO 006 868) where I’d met Graham Pugh on my previous visit.  From Cefn we followed a footpath down a green lane to the bwlch between the hills, past the car next to the bungalow and up to the summit of Gelli Hir.

The footpath from Cefn toward the bwlch between the two hills

The summit area of Gelli Hir is similar to that of Y Gaer as it consists of a 4m x 4m green blob of closely cropped grass.  Once we had levelled the area and found the high point we inserted what is now becoming a customary addition to our surveys; a metal stud that John had bought, this is ideal for soft ground as it creates a point for the spike of the two metre pole to be positioned without the possibility of it slowly sinking a few millimetres in to the ground under the weight of the surveying equipment that is screwed to the top of the pole.

Levelling for summit position on Gelli Hir

Graham and John beside the Leica GS15 at the summit of Gelli Hir

The two hours on the summit of Y Gaer had been slightly chilly so we wrapped up and waited for another two hours of summit data to be collected with the Leica and ten minutes with the Trimble and passed the time with good conversation.  Once sufficient data was stored we packed everything away and made our way back down to the car.  A long day on the hill but good to be out with John and Graham again and to see Eryl for an hour.

LIDAR image of Gelli Hir (SN 999 883)

The Trimble GeoXH 6000 gathering data at the summit of Gelli Hir with Y Gaer in centre background

Survey Result:

Y Gaer (significant name change)

Summit Height:  307.1m (converted to OSGM15, Trimble GeoXH 6000)  307.1m (converted to OSGM15, Leica GS15)

Summit Grid Reference:  SO 01350 87380

Bwlch Height:  215.8m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)

Bwlch Grid Reference:  SO 00054 87410 (from previous Trimble GeoXH 6000 survey)

Drop:  91.3m  (de-twinning with prioritised Hump reclassified to Subhump)

Dominance:  29.74% (Lesser Dominant deletion confirmed)

Gelli Hir (significant name change)

Summit Height:  307.2m (converted to OSGM15, Trimble GeoXH 6000)  307.2m (converted to OSGM15, Leica GS15)

Summit Grid Reference:  SN 99903 88383

Bwlch Height:  182.5m (LIDAR)

Bwlch Grid Reference:  SN 97223 88327 (LIDAR)

Drop:  124.7m  (de-twinning with prioritised Subhump reclassified to Hump)

Dominance:  40.60% (Lesser Dominant addition confirmed)

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

Mapping Mountains – Trimble Surveys – Pumlumon

07.02.14  Y Gaer (SO 013 873), Gelli Hir (SN 999 883) and Cefn Carnedd (SO 015 899)

This is the first of two Trimble surveys of Y Gaer and Gelli Hir, to read the second survey post please click {here}

Y Gaer (SO 013 873)

I’d first visited these hills on the 17.01.04, long before P30’s became fashionable.  On my first visit I’d bagged each from the most convenient parking place, today I wanted to combine them in a circular walk and investigate different approach and descent routes.

As the forecast was the most optimistic for the past few days I took advantage, even though a persistent head cold had plagued me for a number of days.  Hopefully a steady wander in sunshine might sweat the symptoms out of me.

I parked close to the Water Works (SO 021 893) on the outskirts of Llandinam and headed south up the Waen Lane.  I soon realised that the most appropriate footwear for the day was wellies as the fields were awash and particularly muddy.  Leaving the lane a footpath follows the crest of the Y Gaer ridge and eventually enters forestry known as Coed Mawr.  By this stage my boots were covered in liquid mud so I clambered a fence and walked in the field, passing the remains of a house on my way to the highest point.

The summit consists of close cropped grass and is placed near a few trees.  It wasn’t difficult to assess the territory and find the high point.  I’d brought the Draper tripod and external antenna just in case the tree coverage was problematic for the Trimble’s internal antenna.  Deciding not to use the tripod I set the equipment in place and then waited about 20 minutes for it to attain its 0.1m accuracy before pressing ‘Log’ to start gathering data.  This time delay was probably due to the proximity of the trees, every couple of minutes I would sneak up on the Trimble and see if the required accuracy had been attained, only to quickly sneak off again when it had not.  This procedure happened on a number of occasions.  My only companions were an investigative herd of sheep who seemed particularly interested in my exploits.

Looking back toward the high point of Y Gaer

Attentive surveying companions

Once 10 minutes of data was gathered I headed down on footpaths towards the farm named Cefn (SO 006 868) where I surprised Graham Pugh as he came out of a barn full of recently born lambs.  I apologised for surprising him and explained where I had come from and where I was heading.  We were soon talking about the name of the hill, something I hoped to have confirmed and who better to ask than the farmer who lives and works immediately below it.  Graham knew the hill as The Gaer (Y Gaer on the map) after the ancient hill fort north of the summit.  I asked if he’d ever heard of Coed Mawr, he had but only as the name of the farm at (SN 990 889), he certainly didn’t know the hill as Coed Mawr.  When I asked him about the other 308m summit (SN 999 883) he explained that he didn’t know a specific name for it but he’d recently talked with the person from the farm of Coedmawr who had purchased the land and he called it Gelli something.  This last part I found particularly interesting as the Sub-HuMP is currently named Rhos Fawr, this name applies to the farm at SN 996 884 and not the hill.  I’m as guilty as other hill list compiler’s as I’d also used the names of Coed Mawr and Rhos Fawr when compiling the Welsh 300m P30 Hills that was published on Geoff Crowder’s website in 2002.  The Ordnance Survey Seventh Series, New Popular and Historical 1:25,000 maps are all better for name placement when compared to current maps, especially so for the latter of these three.  One tendency with current maps is to align most if not all names horizontally, whereas many of the older maps had ridge names following the ridge, a practice that makes picking the most appropriate name much easier.  Examine these three older maps and see where the name Gelli Hir is placed compared to its current position and you’ll be able to form a much better viewpoint on the most appropriate name of the hill.

Graham Pugh at the farm of Cefn

We spoke for 15 minutes or so and then he started talking about hills with 100m of rise and people who visited the hill from all manner of places, including an elderly man who walked slightly hunched over with the aid of two poles.  Graham had chatted to this person and wondered if he could make it to the top of the hill, the man replied ‘of course I will no problem’.  It was then I showed him the Trimble and explained that I was de-twinning a HuMP, ‘that’s it’ he said ‘the HuMps’ ‘there’re the hills these people go up, they come from all over, many in quite posh cars’, well that last bit rules me out then!

Graham was good enough to show me a short cut over his fields that bi-passed the footpath and headed towards Gwastadcoed (SO 001 872).  Soon I was on another lane and approaching the critical bwlch between the summits of the Twin HuMP.  This is where a 217m spot height appears on the Ordnance Survey enlarged Geograph map.  I always write these posts before processing the data as I don’t want to be influenced by the result, and in the instance of this OS spot height, the processed height is still unknown but the position is absolutely correct as when I walked down the lane, the valley to valley traverse ascended on my right and left and the continuation of the hill to hill traverse carried on up the lane.  I picked my spot beside the road and gathered another 10 minutes of data.

The Trimble GeoXH 6000 beside the road at the bwlch between the Twin HuMP

I then called in at Rhydfaes (SN 997 872) for more place-name enquiries.  Tim had lived in the area all his life and was very helpful, he was under the impression that Coed Mawr related to the wood rather than the hill.

From Tim’s house I followed a track up on the eastern side of Gelli Hir and proceeded to take two data sets.  One on the first high point I reached and the second at the summit of the hill.  Again, my only companions were a number of sheep.  By now the sun was relatively low in the sky casting long shadows and illuminated colour.

Gathering data at the summit of Gelli Hir

Gelli Hir (SN 999 883) seen from the summit of Y Gaer (SO 013 873)

Descending to the track I followed it north-eastward down to another lane where the critical bwlch of Cefn Carnedd is positioned.  If my head cold and time allowed, I wanted to take in this final summit of the day and so I placed the Trimble beside the road and switched it on to gather data, a couple of minutes later there was a rumble and a huge forestry lorry full of felled trees chugged up the narrow lane and missed running over the Trimble by no more than two feet, mind you by this stage I was standing beside it so I was going to get squished first if any squishing was going to take place.  The Trimble has a ‘Pause’ key and I should have used this when the lorry appeared, I didn’t think, my first thought was to stand close to it to stop the lorry causing an expensive accident.  Because of this the data set should be interesting as the lorry blanked out half the sky for 30 seconds.

LIDAR image of Gelli Hir (SN 999 883)

My last hill of the day; Cefn Carnedd proved steep and in a number of places; waterlogged.  The hill has an impressive ancient enclosure taking in its summit that measures 437m by 84m and consists of triple banks and ditches to the north-west.  The high point of the hill is on one of the ancient earthen banks.  The Trimble was set on the high point and gathered 11 minutes of data - modern technology placed on pre-historical earthen ramparts.

The summit of Cefn Carnedd (SO 015 899)

The route back to the car overlooked the Severn valley and the Afon Hafren as it meandered through the flat greenery, over spilling its banks.  It had been an excellent day on fine small hills and a rarity weather wise as the sun shone out of a blue sky.

The Afon Hafren outside of Llandinam

Survey Result: 

Y Gaer (significant name change)

Summit Height:  307.1m (converted to OSGM15)

Summit Grid Reference:  SO 01350 87380

Bwlch Height:  215.8m (converted to OSGM15)

Bwlch Grid Reference:  SO 00054 87410

Drop:  91.3m  (de-twinning with prioritised Hump reclassified to Subhump)

Dominance:  29.74% (Lesser Dominant deletion confirmed)

Gelli Hir (significant name change)

Summit Height:  307.2m (converted to OSGM15)

Summit Grid Reference:  SN 99902 88383

Bwlch Height:  182.5m (LIDAR)

Bwlch Grid Reference:  SN 9723 88327 (LIDAR)

Drop:  124.7m (de-twinning with prioritised Subhump reclassified to Hump)

Dominance:  40.60% (Lesser Dominant addition confirmed)

Cefn Carnedd

Summit Height:  280.0m (converted to OSGM15)

Summit Grid Reference:  SO 01563 89926

Bwlch Height:  203.8m (converted to OSGM15)

Bwlch Grid Reference:  SO 00942 89349

Drop:  76.2m

Dominance:  27.23%

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