Mapping Mountains – Hill Reclassifications – Y Pellennig – The Remotest Hills of Wales

Ynys Arw (SH 266 945) - Pellennig addition 

There has been a new hill that has entered the list of Y Pellennig – The Remotest Hills of Wales, due to a recent Trimble survey.  The hill is situated on Ynysoedd y Moelrhoniaid, this small group of islands are positioned to the north-west, off the north-west coast of Ynys Môn; its name is Ynys Arw.

Ynys Arw (SH 266 945) is the most south-westerly island of this archipelago and has two high points, with the more southerly of these being the highest.  Ynys Arw is tidal and is connected by land to its higher neighbour at low tide, the higher island is where The Skerries Lighthouse is situated and is the highest point of the archipelago and is also listed as a Pellennig hill.

The summit of Ynys Arw is easily accessed at low tide from the Lighthouse, although hands on rock are required to get down to the connecting land that is submerged at high tide.  The ascent from this wet sea weeded land is on rock and then grass that has a multitude of burrowed Tern nests excavated into it.

The high point of Ynys Arw has a 10m ring contour on it and no spot height on current Ordnance Survey maps, it was surveyed with the Trimble GeoXH 6000 at being 15.2m (converted to OSGM15) high, and as the criteria for qualification to the Pellennig list is a hill whose summit is a minimum of 2.5 km from the nearest paved public road and which has a minimum drop of 15m, this hill easily qualifies on the distance criterion and now meets the necessary minimum drop criterion to become the latest entry to the Pellennig list.

This now brings the overall total for Y Pellennig to 168 hills for the Complete list (All Wales), with the total for the Mainland Wales list remaining the same at 124 hills.  The Master List will be duly updated on the Mapping Mountains site.

The full details for the hill are:

Cardinal Island:  Ynysoedd y Moelrhoniaid

Summit Height:  15.2m (converted to OSGM15, Trimble GeoXH 6000)

Name:  Ynys Arw

OS 1:50,000 map:  114

Summit Grid Reference:  SH 26647 94598 (Trimble GeoXH 6000)

Drop:  15.2m (Trimble GeoXH 6000 summit and LIDAR bwlch)

The list of additions in the Y Pellennig list since the 1^st edition of Y Pellennig – The Remotest ills of wales of Wales was published by Europeaklist is as follows:

ADDITIONS

Pen Diban (SH 112 205)

Ynys Arw (SH 266 945)

Ynys Arw (SH 266 945) - the new Pellennig hill

For details on the survey that promoted this hill to Pellennig status please click {here}

© Crown: CHERISH PROJECT 2019. Produced with EU funds through the Ireland Wales Co-operation Programme 2014-2020. All material made freely available through the Open Government Licence.

Myrddyn Phillips and Aled Williams (September 2015)