Mapping Mountains – Summit Relocations – Y Pedwarau

Mynydd Llanybydder (SN 535 395)

There has been a Summit Relocation to a hill that is listed in the Y Pedwarau, with the summit height, position and relocation confirmed by LIDAR analysis initially conducted by Aled Williams and subsequently by Myrddyn Phillips.

LIDAR image of Mynydd Llanybydder

The criteria for the list this summit relocation affects are:

Y Pedwarau - Welsh hills at or above 400m and below 500m in height that have 30m minimum drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and the Introduction to the Mapping Mountains publication of this list appeared on the 30^th January 2017. 

The name of the hill is Mynydd Llanybydder it is situated in the Mynydd Pencarreg range of hills, which are positioned in the central part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with the A 485 road to the west and the B 4337 road to the north-east, and has the town of Llanybydder towards the north north-west.

As the summit of the hill is a part of designated open access land it can in theory be approached from a number of directions, with the easiest via the access track to the high mast which is positioned adjacent to the summit area of this hill.  However, the summit of this hill is now located in a conifer plantation, thankfully its high point is not difficult to reach.

The summit area of this hill has a conifer plantation on its north-eastern side and open hillside on its south-western side, with the latter having an ancient tumulus on it with a triangulation pillar positioned near its high point which is given a 408.617m flush bracket height in the OS Trig Database.  Prior to LIDAR analysis it is this 408m map heighted position that was given as that for the summit in the 1^st edition of Y Pedwarau published by Europeaklist in May 2013.

Extract from the Ordnance Survey 1:25,000 Explorer map showing the summit position in relation to where the trig pillar and ancient tumulus is positioned

LIDAR summit image showing the ancient tumulus just below and to left of centre and the LIDAR summit just above and to right of centre

The Trimble GeoXH 6000 gathering data at the highest ground on top of the ancient tumulus

The LIDAR (Light Detection & Ranging) technique is highly accurate height data that is now freely available for much of England and Wales, and the area of the summit was analysed via LIDAR initially by Aled Williams and then by Myrddyn Phillips, resulting in the below:

LIDAR:  Ancient tumulus with trig pillar:  408.282m at SN 53485 39501

LIDAR:  Position in forestry:  408.510m at SN 53519 39583

LIDAR:  Summit in forestry:  408.700m at SN 53589 39599

During an on-site inspection data were gathered with the Trimble GeoXH 6000 from the highest ground on the ancient tumulus, resulting in:

Trimble:  Ancient tumulus with trig:  408.351m

The summit height produced by LIDAR analysis is 408.7m at SN 53589 39599 and its position in relation to that previously given comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.  As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.

Close up LIDAR summit image of Mynydd Llanybydder

LIDAR contouring implies that ground in the conifer plantation is higher than that at the ancient tumulus, therefore the relocated summit position is at SN 53589 39599 and this is approximately 150 metres north-east from where the previous listed 408m map heighted summit was given in the 1^st edition of the Y Pedwarau published by Europeaklist in May 2013 

 

The Trimble GeoXH 6000 positioned at the LIDAR summit of Mynydd Llanybydder

The full details for the hill are:

Group:  Mynydd Pencarreg

Name:  Mynydd Llanybydder

OS 1:50,000 map:  146

Summit Height:  408.7m (LIDAR)

Summit Grid Reference (New Position):  SN 53589 39599 (LIDAR)

Bwlch Height: c 287m (interpolation)

Bwlch Grid Reference:  SN 56098 40547 (interpolation) 

        

Drop:  c 122m (LIDAR summit and interpolated bwlch)

For details of the survey of this hill

Myrddyn Phillips and Aled Williams (December 2018)

Mapping Mountains – Summit Relocations – Y Pedwarau

Farrington Bank (SO 305 699)

There has been a Summit Relocation to a hill that is listed in the Y Pedwarau, with the summit height, position and relocation confirmed by a survey with the Trimble GeoXH 6000 conducted by Myrddyn Phillipa and which took place on the 15^th February 2018, with the height for the lower summit substantiated from LIDAR analysis conducted by Aled Williams.

The criteria for the list this summit relocation affects are:

Y Pedwarau - Welsh hills at and above 400m and below 500m in height that have 30m minimum drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and the Introduction to the Mapping Mountains publication of this list appeared on the 30^th January 2017. 

The name of the hill is Farrington Bank and it is situated in the Maelienydd range of hills which are also known as the Beacon Hill range, this group of hills is situated in the eastern part of Mid and West Wales (Region B, Sub-Region B1), and the hill is positioned with the B 4365 road to its west, and has the small town of Trefyclo (Knighton) towards the north.

Farrington Bank (SO 305 699)

As the summit of the hill is not on designated open access land permission to visit should be sought, for those wishing to do so access to the hill is relatively easy from the convenience of a high minor road that leads to the access track to The Spaceguard Centre and Observatory that is positioned just to the north-east of the summit.

This hill is given twin 417m map heighted tops on the Ordnance Survey 1:25,000 Explorer map, with the top positioned at SO 305 699 originally given priority status in the listing when published on Geoff Crowder’s v-g.me website, with an accompanying note stating Observatory & trig pillar at second top of same height: SO 307 702.  However, as the top positioned at SO 306 701 has a triangulation pillar this priority status was swapped when the list was renamed as the Y Pedwarau and published by Europeaklist in May 2013.  Both of these tops were surveyed with the Trimble GeoXH 6000, with the result from LIDAR analysis for what proved to be the lower summit also included:

416.700m (converted to OSGM15) at SO 30500 69937 (grazing pasture)

416.499m (converted to OSGM15) at SO 30645 70198 (Trimble for observatory and trig pillar)

416.5m at SO 30659 70187 (LIDAR for observatory and trig pillar)

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

Therefore as the higher top has been confirmed as the summit in the grazing pasture, this is a Summit Relocation for the hill compared to the current listing which gives the top behind the observatory beside the trig pillar as prioritised status.  The relocated summit is approximately 300 metres to the south-west of where the summit is given in the Europeaklist publication of the Y Pedwarau.

The full details for the hill are:

Group:  Maelienydd (Beacon Hill)

Summit Height:  416.7m (converted to OSGM15)

Name:  Farrington Bank

OS 1:50,000 map:  137, 148

Summit Grid Reference (New Position):  SO 30500 69937 

        

Drop:  c 123m

Gathering data at the summit of Farrington Bank (SO 305 699)

Gathering data at the old prioritised summit of Farrington Bank (SO 306 701)

For details on the survey that relocated the summit of this hill

Myrddyn Phillips and Aled Williams (March 2018)

Mapping Mountains – Summit Relocations – Y Pedwarau

Pawl Hir (SO 101 595)

There has been a Summit Relocation to a hill that was surveyed for 400m Sub-Pedwar status with the Trimble GeoXH 6000, with the survey that resulted in this summit relocation taking place on the 3^rd October 2017 in good, clear conditions.

The criteria for the list this hill was surveyed for are:

Y Pedwarau – All Welsh hills at or above 400m and below 500m in height that have 30m minimum drop.  Whilst the criteria for 400m Sub-Pedwar status is all Welsh hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop.

The name of the hill is Pawl Hir and it is situated in the Fforest Glud range of hills which are in the eastern part of Mid and West Wales (Region B, Sub-Region B1), and the hill is positioned between the town of Llandrindod (Llandrindod Wells) to its west north-west and the small community of Hundred House to its south.

Pawl Hir (SO 101 595)

As the summit of the hill is not on designated open access land permission to visit should be sought, for those wishing to do so the nearest public footpath crosses the hill from a west – east direction and just bi-passes the two high points of the hill, one of which is situated on the northern part of the summit area and the other on the southern part, with the easiest and most convenient ascent being from the east following the footpath up the hill from the convenience of a sharp corner on a minor lane, where there is adequate parking for a car.

Prior to the survey with the Trimble GeoXH 6000 the hill was noted with 19m of drop based on the 408m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and the 389m bwlch spot height that appears on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website, this latter map also gives a 407m spot height to the south south-west of the 408m summit spot height.  Therefore, the purpose of the survey was to ascertain the high point of the hill and determine if it had the minimum of 20m of drop required to be classified as a 400m Sub-Pedwar.

In all four points were surveyed for the high point of this hill; one on the northerly land where the 408m spot height appears and three on the southerly land where the 407m spot height appears, these results are given below:

1^st survey, 408m spot height – 404.903m (converted to OSGM15) at SO 10225 59703

2^nd survey, 407m spot height – 405.785m (converted to OSGM15) at SO 10108 59510

3^rd survey, 407m spot height – 405.359m (converted to OSGM15) at SO 10036 59429

4^th survey, 407m spot height – 405.641m (converted to OSGM15) at SO 10027 59400

Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website

The highest height obtained with the Trimble GeoXH 6000 compared to where each spot height appears on the ground is given below:

408m spot height - 404.903m (converted to OSGM15) at SO 10225 59703

407m spot height – 405.785m (converted to OSGM15) at SO 10108 59510

Therefore, the position of the relocated summit is at SO 10108 59510 and is featureless ground consisting of grass and thistles, this position is within the southerly area of the 400m ring contour on Ordnance Survey maps and is close to where the 407m spot height appears on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website, the relocated summit is approximately 235 metres south south-west from where the previously noted summit is positioned.

The full details for the hill are:

Cardinal Hill:  Gilwern Hill

Summit Height:  405.8m (converted to OSGM15)

Name:  Pawl Hir

OS 1:50,000 map:  148

Summit Grid Reference (New Position):  SO 10108 59510

Drop:  16.9m (converted to OSGM15)

The Trimble GeoXH 6000 gathering data at the summit of Pawl Hir with the old position of the summit in the background of this photograph

For details on the survey that confirmed the summit relocation of this hill

Myrddyn Phillips and Aled Williams (December 2017)

Mapping Mountains – Summit Relocations – Y Pedwarau

Llandegle Rocks (SO 132 617)

There has been a Summit Relocation to a hill listed in the Y Pedwarau which was initiated by LIDAR data analysed by Aled Williams and confirmed by a survey with the Trimble GeoXH 6000, with the survey that resulted in this summit relocation taking place on the 3^rd October 2017 in good, clear conditions.

The list that this summit relocation affects is:

Y Pedwarau – All Welsh hills at and above 400m and below 500m in height that have a minimum 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and the Introduction to the Mapping Mountains publication of the list appeared on the 30^th January 2017. 

The name of the hill is Llandegle Rocks and it is situated in the Fforest Glud range, this group of hills is positioned in the eastern part of Mid and West Wales (Region B, Sub-Region B1), and the hill is situated with the small community of Llandegle to the north north-east and Pen-y-bont to the north-west.  The upper part of the hill is made up of an island of designated open access land, with public footpaths leading to it from the west, north, east and south.  

Llandegle Rocks (SO 132 617)

The hill’s summit position was previously given as SO 131 618, this is where the 436m spot height appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, which is adjoined to a triangulation pillar with the flush bracket height of 436.473m.  Ordnance Survey maps also give a separate 430m ring contour towards the south-east that is not spot heighted and which visually is close in height to where the summit was listed. 

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

However, prior to the survey with the Trimble GeoXH 6000 this hill’s summit was analysed using LIDAR data by Aled Williams.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.

 

Aled’s analysis of LIDAR data gives the hill the following details:

Llandegle Rocks (contour ring with trig pillar)

Summit Height:  436.1m

Summit Grid Reference:  SO 13145 61803

Llandegle Rocks (south-east 430m ring contour)

Summit Height:  436.3m

Summit Grid Reference:  SO 13202 61751

Bwlch Height:  345.5m

Bwlch Grid Reference:  SO 11362 59618

Drop:  90.8m

Whilst the height produced by the Trimble GeoXH 6000 appears below:

Llandegle Rocks (contour ring with trig pillar)

Summit Height:  436.258m (converted to OSGM15)

Summit Grid Reference:  SO 13145 61803

Llandegle Rocks (south-east 430m ring contour)

Summit Height:  436.344m (converted to OSGM15)

Summit Grid Reference:  SO 13202 61752

The Trimble GeoXH 6000 gathering data at the old summit position of Llandegle Rocks with the new position for the summit on the left of this photo

Therefore, the position of the relocated summit is at SO 13202 61752 and is featureless ground consisting of grass, this position is within the south-eastern 430m ring contour on Ordnance Survey maps, although no spot height is given to it, the relocated summit is approximately 70 metres south-eastward from where the previously listed summit is positioned.

The full details for the hill are:

Cardinal Hill:  Gilwern Hill

Summit Height:  436.3m (converted to OSGM15)

Name:  Llandegle Rocks

OS 1:50,000 map:  148

Summit Grid Reference (New Position):  SO 13202 61752  

   

Drop:  90.8m

The Trimble GeoXH 6000 gathering data at the new summit position of Llandegle Rocks with the old summit position beside the trig pillar in the background of this photo

For details on the survey that confirmed the summit relocation of this hill

Myrddyn Phillips and Aled Williams (December 2017)