Plynlimon

The highest point of the massif itself is Pen Pumlumon Fawr, which is 752 metres (2,467 ft) above ordnance datum. Its other important peaks are Pen Pumlumon Arwystli, Y Garn, Pen Pumlumon Llygad-bychan and Pumlumon Fach. Bryn yr Ŵyn, or 'hill of the lambs', is a former Dewey in the foothills. The longest river in Britain, the River Severn, has its source on the mountain, as do the rivers Wye and Rheidol. Folklore says there is a sleeping giant in Plynlimon. Plynlimon is anglicised from the Welsh name Pumlumon, which is thought to mean "five tops" or "five beacons". The first element is Old Welsh pimp, meaning "five" (Modern Welsh pump), and the second is llumon, "beacon", an element whose Brittonic equivalent underlies the Scottish hill-names Lomond Hills and Ben Lomond. The Plynlimon area is the source of the rivers Wye, Severn and Rheidol.