Mapping Mountains – Significant Name Changes – 30-99m Twmpau

Gwales (SM 598 094 & SM 598 093) 

There has been a Significant Name Change that is retrospective to a hill that is listed in the 30-99m Twmpau, with the summit height and its location, the drop and status of the hill derived from detail on maps produced from Ordnance Survey data.                       

Gwales (SM 598 094 & SM 598 093)

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

30-99m Twmpau - Welsh hills at or above 30m and below 100m in height that have 30m minimum drop, with an accompanying sub list entitled the 30-99m Sub-Twmpau, with the criteria for this sub category being all Welsh hills at or above 30m and below 100m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. 

30-99m Twmpau by Myrddyn Phillips

The hill is adjoined to the Garn Fawr group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with the nearest minor road on the mainland to its east, and has the town of Hwlffordd (Haverfordwest) on the mainland towards the east north-east. 

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

When the original 30-99m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill appeared under the transposed name of Grassholm Island, which is a prominent name that appears adjacent to this island on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

Grassholm Island

42m

SM598093

157

36

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, with little consideration for the meaning of the name or the language used and where the name was appropriately applied to.  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.

The intricacies of language and prioritising one in favour of another for listing a hill is fraught with complication, with originating Cymraeg names being anglicised and also originating English names being cymricised, examples such as these are more common in border country and especially so for anglicised forms.  There is no steadfast rule that fits all, but as a standard a name that has its origins in the Welsh language and where this is substantiated by either historic documentation and/or contemporary usage should be prioritised in favour of a contemporary anglicised or English version of the name.  Likewise, if a name exists where an element of it is in English and if this name applies to a hill that is situated in a Welsh speaking part of Wales it is standard practice to use a full Welsh term for the name.  It is also standard practice to use a Welsh name for a hill if another name exists that has originated in a different language.

Therefore, the name this hill is now listed by in the 30-99m Twmpau is Gwales, and this was derived from various sources including the Dictionary of the Place-Names of Wales by Hywel Wyn Owen and Richard Morgan and published by Gomer Press. 

 

The full details for the hill are:

Group:  Garn Fawr

Name:  Gwales 

Previously Listed Name:  Grassholm Island   

OS 1:50,000 map:  157

Summit Height:  42m (spot height) 

Summit Grid Reference:  SM 59840 09415 & SM 59825 09366 (spot height)               

Bwlch Height:  N/A (sea level) 

Bwlch Grid Reference:  N/A (sea level) 

Drop:  42m (spot height) 

 

Myrddyn Phillips (June 2026)