Friday, 29 September 2017

Mapping Mountains – Hill Reclassifications – Y Trichant


Bwlch y Cefn Bank (SO 123 608) – Pedwar reclassified to Trichant

There has been a reclassification to the listing of Y Trichant due to analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000.  Y Trichant is the title for the hills in the 300m height band of the Twmpau (thirty welsh metre prominences and upward) and takes in all Welsh hills at or above 300m and below 400m in height that have a minimum 30m of drop, with the introduction to the re-naming of this list appearing on Mapping Mountains on the 13th May 2017.

Prior to analysis of LIDAR data this hill was listed as a Pedwar with c 52m of drop based on the 400m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and an estimated bwlch height of c 348m based on interpolation of bwlch contouring between 340m – 350m.  The criteria for Pedwar status are all Welsh hills at or above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30th January 2017. 

The name of the hill is Bwlch y Cefn Bank and it is situated in the Elfael range of hills with its Cardinal Hill being Gilwern Hill (SO 098 582) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B1).  The hill is positioned above the A 44 road which is to its east and to its north, and the Afon Ieithon (River Ithon) which is to its north-west, with the small community of Llandegley to the north north-east of the hill.

As the summit of the hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so the land to the north-east and the south-west of the hill is a part of designated open access land, and a public footpath crosses between each just to the south-east of this hill’s summit.

The reclassification of Bwlch y Cefn Bank to Trichant status is due to the analysis of 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:


Bwlch y Cefn Bank

Summit Height:  399.0m

Summit Grid Reference:  SO 12367 60871

Bwlch Height:  347.1m

Bwlch Grid Reference:  SO 12752 60893

Drop:  51.9m


Therefore, the 399.0m LIDAR data produced for the summit position at SO 12367 60871 and the 347.1m LIDAR data produced for the bwlch position at SO 12752 60893 gives this hill 51.9m of drop, and as the summit height is below 400m and in the 300m height band it is sufficient for this hill to be reclassified to Trichant status, with the details from the Trimble GeoXH 6000 survey being 399.9m (converted to OSGM15) summit at SO 12369 60880 and 347.2m (converted to OSGM15) bwlch at SO 12752 60893, giving this hill a summit height below 400m.


The full details for the hill are:


Cardinal Hill:  Gilwern Hill 

Summit Height:  399.9m (converted to OSGM15)

Name:  Bwlch y Cefn Bank

OS 1:50,000 map:  148

Summit Grid Reference:  SO 12369 60880

Drop:  52.7m (converted to OSGM15)


Bwlch y Cefn Bank (SO 123 608) is now included in the Y Trichant listing of hills


My thanks to Aled Williams for sending the details of this hill to me



Thursday, 28 September 2017

Mapping Mountains – Hill Reclassifications – Humps


Coed y Cefn (SN 950 682) – Subhump addition

This is the fifteenth 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 conducted.

Coed y Cefn (SN 950 682)

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, and for the reclassifications that affected the Humps the email I posted on the RHB Yahoo Group forum in relation to this hill was dated 12.06.13.

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 an addition to the listing of the Humps (HUndred Metre Prominences) due to consulting the Ordnance Survey enlarged mapping that is hosted on the Geograph website, with these details being posted on the RHB Yahoo Group forum on 12.06.13.

Prior to this notification Mark Jackson had listed this hill with c 89m of drop based on a c 341m estimated summit height and a bwlch height of 252m taken from the spot height that appears on the Ordnance Survey 1:25,000 Explorer map.  However, the Ordnance Survey enlarged mapping hosted on the Geograph website gives this hill a 342m summit spot height and when coupled with its 252m bwlch spot height it gives this hill 90m of drop, which is sufficient for it to be classified as a Subhump.

Extract from the Ordnance Survey enlarged mapping hosted on the Geograph website showing the 342m summit and 252m bwlch spot heights

The hill appeared under the name of Ochr-cefn in the Tumps prior to this notification, with this name having appeared in the 300m Welsh P30 list published on Geoff Crowder’s v-g.me website and which was derived from buildings situated to the west of the hill’s summit.  When this notification was posted on the RHB Yahoo Group forum brief details relating to the hill’s name were included, due to this post the name of the hill now appears as Coed y Cefn.

The hill is adjoined to the Elenydd group of hills and is situated overlooking the A 470 road, the Afon Gwy (River Wye) and the town of Rhaeadr Gwy (Rhayader) which are all towards the east of the hill.

The addition of this hill to Subhump status was accepted by Mark Jackson and the listing of the Humps was updated accordingly.

Coed y Cefn was subsequently surveyed with a Trimble GeoXH 6000 on the 14.04.15, resulting in this hill having a 342.2m (converted to OSGM15) summit height and a 251.3m (converted to OSGM15) bwlch height, with these values giving this hill 90.8m of drop.


Gathering data with the Trimble GeoXH 6000 at the summit of Coed y Cefn


The full details for the hill are:


Name:  Coed y Cefn

Summit Height:  342.1m (as listed in the Humps, 342.2m converted to OSGM15)

OS 1:50,000 map:  136, 147

OS 1:25,000 map:  200

Summit Grid Reference:  SN 95081 68222 (as listed in the Humps)

Drop:  90.8m (converted to OSGM15)



Myrddyn Phillips (September 2017)

Wednesday, 27 September 2017

Mapping Mountains – Hill Reclassifications – Y Pedwarau


Bwlch y Cefn Bank (SO 123 608) – Pedwar reclassified to 390m Sub-Pedwar

There has been a reclassification to the listing of Y Pedwarau due to analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000.  Y Pedwarau is the title for the list of 400m hills of Wales and takes in all Welsh hills at or above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30.01.17.

Accompanying the main Y Pedwarau list are five categories of sub hills, with this hill being reclassified to the 390m Sub-Pedwar categoryThe criteria for 390m Sub-Pedwar qualification is all Welsh hills at or above 390m and below 400m in height that have a minimum 30m of drop.

Prior to analysis of LIDAR data this hill was listed with c 52m of drop based on the 400m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and an estimated bwlch height of c 348m based on interpolation of bwlch contouring between 340m – 350m.

The name of the hill is Bwlch y Cefn Bank and it is situated in the Elfael range of hills with its Cardinal Hill being Gilwern Hill (SO 098 582) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B1).  The hill is positioned above the A 44 road which is to its east and to its north, and the Afon Ieithon (River Ithon) which is to its north-west, and with the small community of Llandegley to the north north-east of the hill.

As the summit of the hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so the land to the north-east and the south-west of the hill is a part of designated open access land, and a public footpath crosses between each just to the south-east of this hill’s summit.

The reclassification of Bwlch y Cefn Bank to 390m Sub-Pedwar status is due to the analysis of 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:


Bwlch y Cefn Bank

Summit Height:  399.0m

Summit Grid Reference:  SO 12367 60871

Bwlch Height:  347.1m

Bwlch Grid Reference:  SO 12752 60893

Drop:  51.9m


Therefore, the 399.0m LIDAR data produced for the summit position at SO 12367 60871 and the 347.1m LIDAR data produced for the bwlch position at SO 12752 60893 gives this hill 51.9m of drop, and as the summit height is below 400m it is insufficient for this hill to retain its Pedwar status, with the details from the Trimble GeoXH 6000 survey being 399.9m (converted to OSGM15) summit at SO 12369 60880 and 347.2m (converted to OSGM15) bwlch at SO 12752 60893, giving this hill a summit height below 400m.


The full details for the hill are:

Cardinal Hill:  Gilwern Hill 

Summit Height:  399.9m (converted to OSGM15)

Name:  Bwlch y Cefn Bank

OS 1:50,000 map:  148

Summit Grid Reference:  SO 12369 60880

Drop:  52.7m (converted to OSGM15)


The total for Y Pedwarau is now 442 hills with ten additions, and fifteen reclassifications to either 400m Sub-Pedwar status or 390m Sub-Pedwar status since publication of the list by Europeaklist in May 2013.

The overall total for the 400m Sub-Pedwarau remains at 218 with 27 hills being added and 22 hills being taken out of this category since publication of the list by Europeaklist in May 2013, whilst the 390m Sub-Pedwar total increases by one to 38 hills.

The list of Pedwar hills is available from the Haroldstreet website (January 2014) with all subsequent changes detailed on the Mapping Mountains site, with the list also having commenced publication on Mapping Mountains on the 30.01.17.

For the additions, reclassifications and deletions to Y Pedwarau reported on Mapping Mountains since the May 2013 publication of the list by Europeaklist please consult the following Change Registers:









Bwlch y Cefn Bank (123 608) is now included in the 390m Sub-Pedwar listing of hills

For details on the survey that confirmed this hill's 390m Sub-Pedwar status

Myrddyn Phillips and Aled Williams (September 2017)

Tuesday, 26 September 2017

Mapping Mountains – Summit Relocations – Tumps


Tumps – Summit Relocations

The Tumps (thirty & upward metre prominences) are all hills in Britain that have a minimum drop of 30m, irrespective of their height.  The list was collated by Mark Jackson and was reliant upon the duplication of many other lists that already existed such as the accumulated listings of the Simms, Deweys, Donald Deweys, Highland Fives, Y Pedwarau, The Fours and Y Trichant, and the posts that have appeared on Mapping Mountains detailing the summit relocations specifically for this list appear below presented chronologically in receding order.







Mapping Mountains - Summit Relocations - Tumps

Elbury Hill (SO 869 558) – recommended summit relocation from Leopard Hill (SO 872 555) - 2nd summit relocation

Survey post for Elbury Hill and Leopard Hill


There has been a recommendation of a Summit Relocation to a hill listed in the Tumps which was initiated by a survey with the Trimble GeoXH 6000 and which took place on the 29th January 2018 in good dry conditions, with no breeze and clear visibility.

The criterion for the list that this recommendation affects is:

Tumps – All British hills with 30m or more of drop.

The list was duplicated, compiled and collated by Mark Jackson and first published in 2009, with the word Tump being an acronym meaning Thirty & Upward Metre Prominences.

The name of the hill is Elbury Hill and it is placed in Central and Eastern England Region 39, with its Parent Hill being Walton Hill (SO 942 798).  The hill is positioned overlooking the city of Worcester and has the B 4637 road to its south-east which is named Tolladine Road in its upper section.

As the summit of the hill is not a part of designated open access land permission to visit should be sought, however the summit area of this hill and that of Leopard Hill are used for recreation purposes, with Elbury Hill having a number of benches positioned around the periphery of its summit for people to sit and admire the view.

The qualifying Tump is currently Leopard Hill (SO 872 555) which is given a 98m summit spot height on contemporary Ordnance Survey maps.  To the north-west of Leopard Hill are further areas of land that have in the main escaped urban development, these are Elbury Hill and Gorse Hill.  Elbury Hill is given a 98m summit spot height on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website, whilst Gorse Hill is given a 92m summit spot height on this same map.

The summit area of Leopard Hill is crowned by a metal fenced water tower, whilst the summit area of Elbury Hill has two large metal fenced compounds housing covered reservoirs, with land between being open.

The summit of Leopard Hill

The summit of Elbury Hill

The summit of Elbury Hill is shown with a triangular symbol on the Ordnance Survey Six-Inch map published in 1886, which is given the height of 323ft (98.5m) on the Six-Inch map published in 1905.  The latter map has a covered reservoir marked to the north of the triangular symbol, whilst the map from 1886 just has the symbol; this implies that the 323ft (98.5m) height was taken to natural ground before the covered reservoir was constructed.  The TrigpointingUK website details a block that replaced a pillar in 1970 and which is adjacent to a mast that stands in one of two covered reservoir compounds, this mast is also recorded in the OS Trig Database at SO 86872 55812, unfortunately a height is not recorded for it.  The 323ft (98.5m) height would have been to the old pillar which is given the position of SO 86915 55816 in TrigpointingUK.

Extract from the Ordnance Survey Six-Map map published in 1886

Extract from the Ordnance Survey Six-Inch map published in 1905

The survey with the Trimble GeoXH 6000 produced the following results:

Leopard Hill:  97.197m (converted to OSGM15) summit at SO 87270 55534

Elbury Hill:  97.435m (converted to OSGM15) summit at SO 86900 55854


Although the recommendation is to swap the position of the col and therefore the drop value and status as Tump of these two hills, the height difference produced by surveying with the Trimble GeoXH 6000 is not great.  However, the resulting data is the best available at hand, with the caveat that higher ground may exist close to where the Trimble was placed on Leopard Hill and that higher ground may exist in the southern compound close to, or at the position of the high mast on top of Elbury Hill.  The added complication are the covered reservoirs on Elbury Hill and whether the open ground between the two compounds can be thought of as being natural.


The full details for the hill are:

Parent Hill:  Walton Hill

Summit Height:  97.4m (converted to OSGM15)

Name:  Elbury Hill

OS 1:50,000 map:  150

Summit Grid Reference (recommended New Position):  SO 86900 55854 
Drop:  c 53m



Myrddyn Phillips (March 2018)






Mapping Mountains - Summit Relocations - Tumps

Caus Castle (SJ 337 077) - 1st summit relocation

Survey post for Caus Castle

Significant Height Revisions post for Caus Castle


There has been confirmation of a Summit Relocation to a hill that is listed in the Tumps (thirty & upward metre prominences)with the summit height, col height and their locations, the drop and status of the hill derived from a Trimble GeoXH 6000 survey and subsequent LIDAR analysis conducted by Myrddyn Phillips.

Caus Castle (SJ 337 077)

The criteria for the list that this summit relocation applies to are:

Tumps.  All hills in Britain that have 30m minimum drop, irrespective of their height.  The list is authored by Mark Jackson and is published and maintained by the DoBIH.

The summit cone of Caus Castle (SO 337 077)

The name the hill is listed by is CausCastle, and it is adjoined to the Stiperstones group of hillswhich are situated in the county of Shropshire close to the Welsh border, and it is positioned with a minor road to its immediate north-west, the A458 road to its north and the B4386 road to its east, and has the village of Westbury towards the north-east.

Prior to the survey with the Trimble GeoXH 6000 this hill was listed with a 223m summit height based on the spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map and which is positioned at SJ 33772 07836.


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

However, it was not until the Trimble GeoXH 6000 survey and subsequent LIDAR analysis that the details for this hill could be accurately 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 Caus Castle (SJ 337 077)

LIDAR analysis gives the highest ground on this hill as 232.1m with the Trimble giving the summit positioned at SJ 33713 07792, and this position in relation to the position of the 223m spot height comes within the parameters of the Summit Relocations used within this page heading, these parameters are:

The term Summit Relocations applies to when the high point is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, 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.

The summit where the 223m Ordnance Survey spot height appears

The Trimble GeoXH 6000 on the summit of Caus Castle

Therefore, the summit height produced by LIDAR analysis is 232.1m with the Trimble GeoXH 6000 giving the summit positioned at SJ 33713 07792.  This position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is positioned to a different feature and is approximately 70 metres south-westward from where the 223m spot height appears.

The full details for the hill are:

Group:  Stiperstones

Name:  Caus Castle

OS 1:50,000 map:  126

Summit Height:  232.1m (LIDAR)

Summit Grid Reference (New Position):  SJ 33713 07792 (Trimble GeoXH 6000)

Col Height:  180.4m (converted to OSGM15, Trimble GeoXH 6000)

Col Grid Reference:  SJ 33384 07622 (Trimble GeoXH 6000)

Drop:  51.7m (LIDAR summit and Trimble GeoXH 6000 col)


Myrddyn Phillips (April 2015)