Wales’ Newest P30 – Mynydd Tŷ’r Sais (SH 855 004)

 

Wales’ Newest P30 – Mynydd Tŷ’r Sais (SH 855 004)

In October 2019 whilst descending Corun y Ffridd (SH 873 018) I looked south-westward toward a gently rising pastured slope that culminated in a shapely summit and wondered about the hill’s drop value.  At that time it was listed as a Sub-Trichant with 26m of drop based on a 359m summit and a 333m bwlch spot height, with the latter appearing on the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map.

Mynydd Tŷ'r Sais (SH 855 004) from the descent of Corun y Ffridd

 

The hill in question is named Mynydd Tŷ’r Sais and having seen it I made a mental note to visit and survey its summit and bwlch to ascertain its drop value.  However, such mental notes are aplenty and my interest in this hill was not prioritised until Ronnie Bowron contacted me.  Ronnie had been working his way through the details in Joe Nuttall’s spreadsheet created from his summit analysis programme, and although this hill is not currently covered by LIDAR the height given it and Ronnie’s interpolation of its bwlch height meant that the hill’s drop value in every likelihood exceeded 30m, therefore becoming a Trichant.  Ronnie kindly passed these details on to me and I told him I would survey it once the Covid-19 restrictions permitted. 

Mynydd Tŷ'r Sais from the north-west

With the Stay at Home advice changing to Stay Local on the 13^th March and changing to unrestricted travel throughout Wales on the 27^th March, it meant that I could visit and survey this hill at the first convenient weather window, this was on the 30^th March. 

One summit data set, and four bwlch data sets from three different positions all on the hill to hill traverse were taken with the Trimble GeoXH 6000, resulting in:

 

362.182m summit at SH 85514 00483 

1^st bwlch survey:  330.153m at SH 86150 00679 (average of two data sets) 

2^nd bwlch survey:  329.944m at SH 86220 00690 

3^rd bwlch survey:  330.099m at SH 86245 00694 

 

The summit of Mynydd Tŷ’r Sais is easily identified and consists of grass two metres from the upper ridge fence, the hill’s bwlch consists of closely cropped grass and has slight undulations, hence the three positional surveys. 

The Trimble GeoXH 6000 gathering data at the summit of Mynydd Tŷ'r Sais

The Trimble GeoXH 6000 gathering data at the bwlch of Mynydd Tŷ'r Sais

The Trimble GeoXH 6000 survey gives this hill 32.2m of drop; therefore this hill is reclassified from Sub-Trichant to Trichant status and in the process becomes Wales’ newest P30. 

 

Thanks to Ronnie Bowron for sending me his evaluation of this hill’s details.

 

Myrddyn Phillips (April 2021)