Y Llethr is the highest

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited Summit (topography), summit area, and ...

in the Rhinogydd range of

Snowdonia Snowdonia or Eryri (), is a mountainous region in northwestern Wales and a national park of in area. It was the first to be designated of the three national parks in Wales, in 1951. Name and extent It was a commonly held belief that the nam ...

, in north

Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...

. The summit consists of a flat grassy top marked only by a small

cairn A cairn is a man-made pile (or stack) of stones raised for a purpose, usually as a marker or as a burial mound. The word ''cairn'' comes from the gd, càrn (plural ). Cairns have been and are used for a broad variety of purposes. In prehis ...

. The

summit A summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. The topography, topographic terms acme, apex, peak (mountain peak), and zenith are synonymous. The term (mountain top) is generally used ...

is more in keeping with its southern flanks than its rugged northern approach. The shortest route to the summit goes from the valley of

Cwm Nantcol Cwm Nantcol is a valley in the Ardudwy area of the county of Gwynedd in Wales. It lies in the Rhinogydd range of mountains in Snowdonia and carries the Afon Cwmnantcol. At the head of Cwn Nantcol is the Bwlch Drws Ardudwy pass, from where it is ...

in the west, either directly or via Bwlch Drws Ardudwy and over the mountain of

Rhinog Fach Rhinog Fach is a mountain in Snowdonia, North Wales and forms part of the Rhinogydd. Technically, Rhinog Fach is a subsidiary summit of Y Llethr, but is a Marilyn. To the north lies its higher cousin Rhinog Fawr, separated by the shapely pass o ...

. To the south lies the mountain of

Diffwys Diffwys is a mountain in Snowdonia, Wales, near Barmouth and forms part of the Rhinogydd. On the north side is an exposure of the Caerdion Syncline. It is technically a subsidiary summit of Y Llethr, missing Marilyn status by 2m. It is ther ...

, to the south-east lies the mountain of Y Garn, to the north lies Rhinog Fach and to the west lies the hill of Moelfre.Nuttall, John & Anne (1999). The Mountains of England & Wales - Volume 1: Wales (2nd edition ed.). Milnthorpe, Cumbria: Cicerone. .

References

Dyffryn Ardudwy Ganllwyd Llanbedr Mountains and hills of Gwynedd Mountains and hills of Snowdonia Hewitts of Wales Marilyns of Wales Nuttalls {{Gwynedd-geo-stub