Mapping Mountains – Summit Relocations – Y Trichant – The 300m Hills of Wales

 

Top Field (SJ 070 055) 

There has been confirmation of a summit position whose details can be included as a Summit Relocation to a hill that is listed in the Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Top Field (SJ 070 055)

The criteria for the list this summit relocation affects are:

Y Trichant- The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13^th May 2017. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Top Field and this was derived from local enquiry, and it is adjoined to the Carnedd Wen group of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is encircled by minor roads, with the A458 road further to its north and the B4389 road further to its east, and has the small town of Llanfair Caereinion towards the east north-east. 

When the original 300m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to meet the criteria then used for the main P30 category. 

When the P30 lists were standardised, and interpolated heights and drop values also included, this hill was listed with an estimated c 32m of drop based on the 335m summit spot height positioned at SJ 07085 05586 and an estimated c 303m bwlch height based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

However, it was not until LIDAR became available 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 image of Top Field (SJ 070 055)

When on the hill the position of the summit given by LIDAR was surveyed using the Trimble GeoXH 6000 as well as another position that looked of similar height.  The second position was to an elevated mound above a small quarry and upon investigation it was decided that this was man-made.

 

The result for each position is given below: 

Natural summit:  333.257m at SJ 07082 05572 

Man-made elevated mound:  333.339m at SJ 07203 05559

 

The result produced by LIDAR analysis gives this hill a summit height of 333.1m, and as the natural summit has now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are: 

The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, to a different feature such as in a conifer plantation, placed within a different map contour, to a different point where a number of potential summit positions are within close proximity, or when natural ground or 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, 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. 

Gathering data with the Trimble GeoXH 6000 at the natural summit of Top Field

Gathering data with the Trimble GeoXH 6000 at the man-made mound

Therefore, the listed summit height of this hill is 333.3m and its confirmed position is SJ 07082 05572, this position is given a spot height on contemporary Ordnance Survey maps and is approximately 80 metres westward from where a slightly higher man-made mound is positioned. 

 

The full details for the hill are:

Group:  Carnedd Wen 

Name:  Top Field 

OS 1:50,000 map:  125

Summit Height:  333.3m (converted to OSGM15, Trimble GeoXH 6000)                                                      

Summit Grid Reference (Confirmed Position):  SJ 07082 05572 (Trimble GeoXH 6000) 

Bwlch Height:  301.1m (LIDAR) 

Bwlch Grid Reference:  SJ 06237 05273 (LIDAR) 

Drop:  32.2m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

Myrddyn Phillips (March 2021)

 

Mapping Mountains – Significant Name Changes – Y Trichant – The 300m Hills of Wales

 

Top Field (SJ 070 055) 

There has been a Significant Name Change to a hill that is listed in the Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Top Field (SJ 070 055)

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

Y Trichant – The 300m Hills of Wales.  Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13^th May 2017. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The hill is adjoined to the Carnedd Wen group of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is encircled by minor roads, with the A458 road further to its north and the B4389 road further to its east, and has the small town of Llanfair Caereinion towards the east north-east. 

The hill appeared in the original Welsh 300m P30 list published on Geoff Crowder’s v-g.me website, under the invented and transposed name of Bryn Rhiw-hiriaeth-uchaf, with an accompanying note stating; Name from buildings to the East.

Bryn Rhiw-hiriaeth-uchaf

335m

SJ071055

125

215

Name from buildings to the East

 

During my early hill listing I thought it appropriate to either invent a name for a hill, or use a name that appeared near to the summit of the hill on Ordnance Survey maps of the day.  My preference was to use farm names and put Pen, Bryn or Moel in front of them and as in this instance transpose the name of a farm and add the word Bryn.  This is not a practice that I now advocate as with time and inclination place-name data can be improved either by asking local people or by examining historic documents, through this form of research an appropriate name for the hill can usually be found. 

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

This was one of a number of hills visited in the company of Alex Cameron during a day’s hill bagging.  After visiting the summit we headed back to my car where Alex put a brew on and whilst enjoying this and assorted accompaniments a tractor appeared chugging up the lane, once it safely negotiated the narrow gap between the paved section of road and my car I flagged it down.  The person driving the tractor was the local farmer; Owen Evans and he told me that unsurprisingly the hill has no individual name, but the field where the summit of the hill is situated is known as Top Field. 

Owen Evans

Therefore, the name this hill is now listed by in the Y Trichant – The 300m Hills of Wales is Top Field, and this was derived from local enquiry. 

 

The full details for the hill are: 

Group:  Carnedd Wen 

Name:  Top Field 

Previously Listed Name:  Bryn Rhiw-hiriaeth-uchaf 

OS 1:50,000 map:  125

Summit Height:  333.3m (converted to OSGM15, Trimble GeoXH 6000)                                                           

Summit Grid Reference:  SJ 07082 05572 (Trimble GeoXH 6000) 

Bwlch Height:  301.1m (LIDAR) 

Bwlch Grid Reference:  SJ 06237 05273 (LIDAR) 

Drop:  32.2m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

Myrddyn Phillips (March 2021) 

Mapping Mountains – Hill Reclassifications – Y Trichant – The 300m Hills of Wales

 

Top Field (SJ 070 055) – Sub-Trichant reclassified to Trichant

There has been confirmation of a reclassification to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Top Field (SJ 070 055)

The criteria for the list that this reclassification applies to are: 

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13^th May 2017. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Top Field and this was derived from local enquiry, and it is adjoined to the Carnedd Wen group of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is encircled by minor roads, with the A458 road further to its north and the B4389 road further to its east, and has the small town of Llanfair Caereinion towards the east north-east. 

When the original 300m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to meet the criteria then used for the main P30 category. 

When the P30 lists were standardised, and interpolated heights and drop values also included, this hill was listed with an estimated c 32m of drop based on the 335m summit spot height and an estimated c 303m bwlch height based on interpolation of 10m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

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

However, it was not until LIDAR became available 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 image of Top Field (SJ 070 055) 

The result produced by LIDAR analysis gives this hill 32.0m of drop with a summit height of 333.1m, and as the summit has now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes. 

The Trimble GeoXH 6000 gathering data at the summit of Top Field

Therefore, the confirmation of the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis and a Trimble GeoXH 6000 survey, resulting in a 333.3m summit height and a 301.1m bwlch height, with these values giving this hill 32.2m of drop, which is sufficient for it to be classified as a Trichant.

 

The full details for the hill are: 

Group:  Carnedd Wen 

Name:  Top Field 

OS 1:50,000 map:  125

Summit Height:  333.3m (converted to OSGM15, Trimble GeoXH 6000)                                          

Summit Grid Reference:  SJ 07082 05572 (Trimble GeoXH 6000) 

Bwlch Height:  301.1m (LIDAR) 

Bwlch Grid Reference:  SJ 06237 05273 (LIDAR) 

Drop:  32.2m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

Myrddyn Phillips (March 2021)

 

 

 

 

 

 

 

 

 

Mapping Mountains – Trimble Surveys – Carnedd Wen

 

15.09.20  Top Field (SJ 070 055)  

Top Field (SJ 070 055)

This was the seventh of a planned thirteen hills that Alex and I hoped to visit during the day, with me sitting out three of these as they had recently been Trimbled.  Alex had navigated the short distance from our previous hill; Caer Wedyn (SJ 095 047) on the narrow lanes that pre-dominate much of the land hereabouts, and I parked in a passing place close to the entrance track to the old farm of Rhiw-hiriaeth-uchaf after Alex had removed a large tangled tree branch that was lodged in the soon to be parking place. 

It was only a short walk on the narrow lane to the access track that swept up the northern flank of the hill toward the old farm which was tucked away out of sight under the summit to the south. 

Alex heading up the start of the access track toward the summit of Top Field

Prior to our visit I’d examined LIDAR and produced data for this hill’s summit and bwlch, and now with the grid co-ordinates produced by LIDAR analysis we zeroed in on the high point.  This consists of grass and as I set the Trimble up a small herd of cows slowly headed our way. 

LIDAR image of Top Field

After asking Alex if he could usher the cows a safe distance from the survey equipment I waited for the Trimble to achieve the 0.1m accuracy level before data should be logged, and once this appeared on the screen I pressed ‘Log’ and retreated to join Alex who was sitting admiring the view. 

With the cows a safe distance away the Trimble could start gathering data

Gathering data at the summit of Top Field

Away to our north Moel Bentyrch dominated the view with its greyed scree and crags on fine display, with the distant outline of ridges and summits beyond.  However, to our west a grey murk had appeared that forever crept nearer.  This looked like cloud bearing rain which was surprising as rain was not forecast. 

Moel Bentyrch

Once the Trimble had gathered and stored its allotted data we headed toward the access track leading to the farm.  From this viewpoint it looked as if the farm required quite a distance to walk, therefore we headed back with intention to use the track back toward the car. 

On our way Alex noticed a vegetated knoll above a small quarry and as this looked a similar height to the point that had just been Trimbled, we headed toward it.  Arriving at the knoll we both thought it probably consisted of debris from the quarry, but as we were now there we decided to gather data. 

Gathering data at the top of the knoll

The farm was now directly below us and as the Trimble beeped away gathering individual data I headed down the continuation of the field to see if I could access it from this direction.  I couldn’t due to wired fences and therefore made my way back to join Alex. 

Once the Trimble was packed away I decided to walk down the track to the farm to make place-name enquiries whilst Alex headed back to the car to get a brew on.  Having knocked at the front door of the old farm and getting no reply I slowly made my way back up the track and decided to get a third data set from where we both considered the highest part of natural ground was positioned at the base of the small vegetated knoll. 

Gathering data at the base of the knoll

After the third data set was taken I sauntered back over the hill and joined the access track and headed down to the narrow lane and the car where Alex duly gave me a welcome large cup of tea. 

Getting the brew on

We stood and chatted whilst sipping on tea and tucking in to the variety of food on offer which included Alex’ Mum’s bara brith and an assortment of crisps, boiled eggs, sandwiches and bananas. 

During our lunch break a tractor appeared chugging up the lane, once it safely negotiated the narrow gap between the paved section of road and my car I flagged it down.  The person driving the tractor was the local farmer; Owen Evans and he told me that unsurprisingly the hill has no individual name, but the field where the summit of the hill is situated is known as Top Field. 

Owen Evans

The day was proving productive with lots of hills being visited and chance encounters with farmers.  The summit of our next hill was beside a track leading to a farm.  I wanted to visit this farm to make place-name enquiries as I’d passed this way a few weeks before and due to the oppressive heat I decided to press on rather than face the re-ascent of the steep track leading down to the farm house. 

 

Survey Result: 

 

Top Field (significant name change)  

Summit Height:  333.3m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SJ 07082 05572 (Trimble GeoXH 6000) (summit relocation confirmed)

Bwlch Height:  301.1m (LIDAR)

Bwlch Grid Reference:  SJ 06237 05273 (LIDAR)

Drop:  32.2m (Trimble GeoXH 6000 summit and LIDAR bwlch) (Sub-Trichant reclassified to Trichant)

Dominance:  9.65% (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

 

For further details please consult the Trimble Survey Spreadsheet