Mapping Mountains – Significant Name Changes – Y Pedwarau – The 400m Hills of Wales and Y Trechol – The Dominant Hills of Wales

Mynydd Epynt (SN 961 464)

There has been a Significant Name Change to a hill that is listed in the Y Pedwarau - The 400m Hills of Wales and the Y Trechol - The Dominant Hills of Wales, with the summit height, bwlch height and their locations, the drop, dominance and status of the hill derived from a Trimble GeoXH 6000 summit survey and LIDAR bwlch analysis conducted by Myrddyn Phillips.  With the change in the listed summit height initiated by LIDAR analysis conducted by Aled Williams.

Mynydd Epynt (SN 961 464)

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

Y Pedwarau – The 400m Hills of Wales.  Welsh hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list are five categories of sub hills, with this hill being included in the 400m Sub-Pedwar category.  The criteria for this sub category being all Welsh hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is published on Mapping Mountains in Google Doc format.

Y Pedwarau - The 400m Hills of Wales by Myrddyn Phillips and Aled Williams

Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3^rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The hill is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region C2, Sub-Region C2A), and it is positioned with the B4519 road to its north-east, and has the town of Llanfair-ym-Muallt (Builth Wells) towards the north-east.

The hill appeared in the original Welsh 400m P30 list compiled by Myrddyn Phillips and published on Geoff Crowder’s v-g.me website, under the transposed name of Mynydd Epynt, which is a prominent name that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

Extract from the Ordnance Survey 1:50,000 Landranger map

The hill was listed in the 1^st edition of the Y Pedwarau published by Europeaklist in May 2013 under the name of Clepyn Melyn, with an accompanying symbol designating that this name was sourced from local enquiry.

The name Clepyn Melyn applies to a patch of land near to the summit of this hill, and as such this name was used for that of the hill as it was considered its main named feature.  However, since publication of the 1^st edition of Y Pedwarau by Europeaklist a number of names have been under review, including this one, and as the summit of this hill is the highest part of the entire mountain known as Mynydd Epynt this name is now preferred to that previously used.

Therefore, the name this hill is now listed by in the Y Pedwarau – The 400m Hills of Wales and the Y Trechol – The Dominant Hills of Wales is Mynydd Epynt, and this was derived from the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

The full details for the hill are:

Group:  Mynydd Epynt

Name:  Mynydd Epynt

Previously Listed Name:  Clepyn Melyn

OS 1:50,000 map:  147

Summit Height:  475.7m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 96124 46428 (Trimble GeoXH 6000)  

Bwlch Height:  277.9m (LIDAR)

Bwlch Grid Reference:  SN 84054 43300 (LIDAR) 

Drop:  197.8m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  41.58% (Trimble GeoXH 6000 summit and LIDAR bwlch)

Myrddyn Phillips and Aled Williams (January 2020)

Mapping Mountains – Trimble Surveys – Mynydd Epynt

28.12.17  Mynydd Epynt (SN 961 464, previously Trimbled), Banc y Cwm (SN 968 470) and Pt. 467.0m (SN 975 473)

Banc y Cwm (SN 968 470)

At the uppermost cattle grid the car started to slide and did so for the next three or four attempts, below was an ice and snow encrusted strip of tarmac that led to friendlier climes below, a 100 metres or so down the road was a sharp corner, below this was a car near a bog in a field and stuck firmly on the hillside; an example of the treacherous road conditions that I was now encountering.

Overshooting the corner .....

..... and coming to a halt near a decidedly unpleasant looking bog

I was with two friends and we were hoping to visit a number of hills on Mynydd Epynt; a land out of bounds for much of the year, but one whose hills are accessible over the Christmas period.

Slowly reversing the car we made progress back down the hill to a relatively wide and flat part of snow that gave a chance to at least face forward going downhill, the remainder of the journey to the valley below was in first gear, I felt relieved when we pulled up beside a public footpath sign which would be our route back after visiting the hills above.

Walking back up the road gave a chance to admire Cwm Graig Ddu as it swept up toward Banc y Cwm; a 467m map heighted Pedwar.  The conditions were wintery with snow on the hills and a fast changing sky above, as its calm hues were rapidly overtaken by a thick deep grey westerly cloud bank heralding more snow, and as we steadily gained height large flakes slowly fell.

Heading back up the road

Cwm Graig Ddu

The fresh snow only lasted a few minutes but gave an appealing gentleness to the land; it was replaced with a beautiful sky with winter cloud sticking to far off hillsides and misted patches slowly ebbing over others.  Patches of blue broke out above, but the westerly mass of grey was forever slowly edging east.

Cresting the top of the road we headed south-west toward the high point of the Epynt, following the continuation of a paved road toward its summit.  Reaching the top the view opened up with a white land stretching further west and south, it was good to be out on the hill and the conditions were proving just ideal with enough snow to enjoy but not to hinder.

Looking south from the high point of Mynydd Epynt

Banc y Cwm from near the high point of Mynydd Epynt

Banc y Cwm looked almost alpine like as we retraced our steps back to the top of the road, its rounded profile smoothed white, the next stage of the walk was to survey the connecting bwlch between Banc y Cwm and Mynydd Epynt.  Thankfully I’d come prepared with a ten figure grid reference for where the map indicates the bwlch to lie between the start of two streams, with the land hereabouts consisting of large snow bound tussocks.

Banc y Cwm from the approach to its critical bwlch

Gathering data at the critical bwlch of Bank y Cwm

Once data were stored and the Trimble packed away I headed toward the summit following footsteps in the snow.  The summit of Banc y Cwm is flattish in nature with undulations this way and that and is close to a large squared block of conifers which is one of many on the Epynt.  I took two data sets from the summit area before the three of us headed down to the continuation of the track leading to the next bwlch to survey. 

Gathering data at the summit of Banc y Cwm

On the way down a Landrover drove up behind the square blocked conifer plantation and the distinctive call of a farmer could be heard calling sheep toward him for feed.  Not wanting to pass an opportunity to make place-name enquiries two of us headed his way, coincidentally I’d met the farmer a number of years ago whilst making place-name enquiries and he had then been a tremendous help, giving many names where none exist on the map.  We chatted for some time as he dropped a salt lick off for the sheep; it was good to see him again after so many years.

Preparing for feeding time

Waving our goodbye’s we headed back on to the track which headed north-east toward the second bwlch, this again consisted of large snow bound tussocks, but at least a small stream gave a clue toward its critical point.  As the Trimble gathered data I stood back and looked out on the mass of grey winter cloud that had formed and remained for much of the day over the Elenydd to the north.

Pt. 467.0m (SN 975 473)

Gathering data at the critical bwlch of Pt. 467.0m (SN 975 473)

Just one survey remained and that was for the second of the 467m map heighted hills, we followed the edge of another square blocked conifer plantation toward the summit which is crowned by a trig pillar.  The high point was about one metre from its base, and once the Trimble had gathered its allotted data and packed away it was time to head down.

Gathering data at the summit of Pt. 467.0m (SN 975 473)

Snow slopes led us down to a public footpath to the north which joined another leading steeply down via a narrow path to the dirtied snow below where a number of friendly horses made their way toward us.

Leaving the summit and heading down

The snow capped Elenydd in the distance

The lower fields led to a minor lane which gained height to the awaiting car, as I slowly plodded up the road the sun dimmed its light and gently fell behind the hill ridge that we had just descended from, it was a fine end to another good day on the hill.

The last glimmer of sun

Survey Result:

Mynydd Epynt (1st significant name change) (2nd significant name change)

Summit Height:  475.7m (converted to OSGM15, previous Trimble GeoXH 6000 survey) (significant height revision)

 

Summit Grid Reference:  SN 96124 46428 (previous Trimble GeoXH 6000 survey)

Bwlch Height:  277.9m (LIDAR)

Bwlch Grid Reference:  SN 84054 43300 (LIDAR)

Drop:  197.8 (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  41.58% (Trimble GeoXH 6000 summit and LIDAR bwlch)

Banc y Cwm (significant name change)

Summit Height:  465.9m (converted to OSGM15)

Summit Grid Reference:  SN 96824 47007

Bwlch Height:  433.4m (converted to OSGM15)

Bwlch Grid Reference:  SN 96584 46748

Drop:  32.5m 

Dominance:  6.98%

Pt. 467.0m

Summit Height:  467.0m (converted to OSGM15)

Summit Grid Reference:  SN 97543 47378

Bwlch Height:  419.7m (converted to OSGM15)

Bwlch Grid Reference:  SN 97192 47333

Drop:  47.3m

Dominance:  10.12%

For further details please consult the Trimble Survey Spreadsheet

Mapping Mountains – Significant Height Revisions – Y Pedwarau - The 400m Hills of Wales and Y Trechol - The Dominant Hills of Wales

Mynydd Epynt (SN 961 464)

There has been a Significant Height Revision to a hill that is listed in the Y Pedwarau - The 400m Hills of Wales and the Y Trechol - The Dominant Hills of Wales, with the summit height, bwlch height and their locations, the drop, dominance and status of the hill derived from a Trimble GeoXH 6000 summit survey and LIDAR bwlch analysis conducted by Myrddyn Phillips.  With the change in the listed summit height initiated by LIDAR analysis conducted by Aled Williams.

Mynydd Epynt (SN 961 464)

The criteria for the two listings that this height revision applies to are:

Y Pedwarau – The 400m Hills of Wales.  Welsh hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list are five categories of sub hills, with this hill being included in the 400m Sub-Pedwar category.  The criteria for this sub category being all Welsh hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is published on Mapping Mountains in Google Doc format.

Y Pedwarau - The 400m Hills of Wales by Myrddyn Phillips and Aled Williams

Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3^rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Mynydd Epynt, and it is adjoined to its own group of hills; Mynydd Epynt, which are situated in the central part of South Wales (Region C2, Sub-Region C2A), and it is positioned with the B4519 road to its north-east, and has the town of Llanfair-ym-Muallt (Builth Wells) towards the north-east.

When the original 400m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website, this hill was included in the main P30 list with a summit height of 478m, based on the spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

Extract from the Ordnance Survey 1:25,000 Explorer map

However, it was not until LIDAR became available and the subsequent Trimble GeoXH 6000 survey that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

LIDAR summit image of Mynydd Epynt (SN 961 464)

The summit height produced by the Trimble GeoXH 6000 is 475.7m positioned at SN 96124 46428, and this comes within the parameters of the Significant Height Revisions used within this page heading, these parameters are:

The term Significant Height Revisions applies to any listed hill whose interpolated height and Ordnance Survey, Harvey or other interactive map summit spot height has a 2m or more discrepancy when compared to the survey result produced by the Trimble GeoXH 6000 or analysis of data produced via LIDAR.  Also included are hills whose summit map data is missing an uppermost ring contour when compared with the data produced by the Trimble or by LIDAR analysis.

The Trimble GeoXH 6000 gathering data at the summit of Mynydd Epynt (SN 961 464)

Therefore, the new listed summit height of this hill is 475.7m and this was derived from a Trimble GeoXH 6000 survey, this is 2.3m lower than the previously listed summit height, which was based on the 478m spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

The full details for the hill are:

Group:  Mynydd Epynt

Name:  Mynydd Epynt

OS 1:50,000 map:  147

Summit Height (New Height):  475.7m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 96124 46428 (Trimble GeoXH 6000)  

Bwlch Height:  277.9m (LIDAR)

Bwlch Grid Reference:  SN 84054 43300 (LIDAR) 

Drop:  197.8m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  41.58% (Trimble GeoXH 6000 summit and LIDAR bwlch)

Myrddyn Phillips and Aled Williams (January 2017)

Mapping Mountains – Significant Name Changes – Y Pedwarau - The 400m Hills of Wales and Y Trechol - The Dominant Hills of Wales

Clepyn Melyn (SN 961 464)


This hill is now listed as Mynydd Epynt, with the details below kept for historic value

There has been a Significant Name Change to a hill that is listed in the Y Pedwarau - The 400m Hills of Wales and the Y Trechol - The Dominant Hills of Wales, with the summit height, bwlch height and their locations, the drop, dominance and status of the hill derived from a Trimble GeoXH 6000 summit survey and LIDAR bwlch analysis conducted by Myrddyn Phillips.  With the change in the listed summit height initiated by LIDAR analysis conducted by Aled Williams.

Mynydd Epynt (SN 961 464)

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

Y Pedwarau – The 400m Hills of Wales.  Welsh hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list are five categories of sub hills, with this hill being included in the 400m Sub-Pedwar category.  The criteria for this sub category being all Welsh hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is published on Mapping Mountains in Google Doc format.

Y Pedwarau - The 400m Hills of Wales by Myrddyn Phillips and Aled Williams

Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3^rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The hill is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region C2, Sub-Region C2A), and it is positioned with the B4519 road to its north-east, and has the town of Llanfair-ym-Muallt (Builth Wells) towards the north-east.

The hill appeared in the original Welsh 400m P30 list compiled by Myrddyn Phillips and published on Geoff Crowder’s v-g.me website, under the transposed name of Mynydd Epynt, which is a prominent name that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

Hill list authors are prone to list a hill by the name that appears nearest to its summit on contemporary Ordnance Survey maps, with little consideration for its local or historical confirmation, or whether map placement is appropriate, and in the case of Mynydd Epynt the name is also associated with the hill range that it is a part of.  

Extract from the Ordnance Survey 1:25,000 Explorer map

However, place-name data can be improved by asking local people and examining historical documents, and in the case of this hill it was a local farmer who gave the name Clepyn Melyn for land near to the summit of the hill, which to the authors knowledge is the main named feature of this hill and therefore appropriate to use for listing purposes.

Therefore, the name this hill is listed by in the Y Pedwarau - The 400m Hills of Wales and Y Trechol - The Dominant Hills of Wales is Clepyn Melyn and this was derived from local enquiry.

The full details for the hill are:

Group:  Mynydd Epynt

Name:  Clepyn Melyn

Previously Listed Name:  Mynydd Eppynt 

OS 1:50,000 map:  147

Summit Height:  475.7m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 96124 46428 (Trimble GeoXH 6000)  

Bwlch Height:  277.9m (LIDAR)

Bwlch Grid Reference:  SN 84054 43300 (LIDAR) 

Drop:  197.8m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  41.58% (Trimble GeoXH 6000 summit and LIDAR bwlch)

Myrddyn Phillips and Aled Williams (January 2017)