Walk Pumlumon – from summit to source


Pumlumon (pronounced “Pimlimon”, meaning ‘five peaks’ and often anglicised to “Plynlimon”) dominates the wild, empty uplands of mid-Wales. Its windswept summit, Pen Pumlumon Fawr (752m/2467ft) is the highest point in the Cambrian Mountains, while its flanks give rise to three major rivers; the Rheidol, the Wye and the Severn (the UK’s longest river at 220 miles). This walk visits both the highest point on the Pumlumon massif and the headwaters of the River Severn, from summit to source.


Starting near the Nant y Moch reservoir, our route heads directly for the summit. On a clear day the views are spectacular, ranging out over the whole of Cardigan Bay, south to the Brecon Beacons and north to the mountains of Snowdonia. However, on a bad day it can be a challenge just to stay upright!

We continue over the broad-backed grassy summit ridge to another major top, Pen Pumlumon Arwystli before dropping down to visit the source of the River Severn, rising from a vast area of upland blanket peat bog. There are several options for our return journey, which will largely be determined by weather and ground conditions on the day: along the remote, pathless and often wet Hengwm valley (gaiters recommended!), via the shores of glacial lake Llyn Llygad Rheidol or even back over the main summit.

A route of approx. 10 miles/16km with 2200ft/670m of ascent over grassy hillside and occasionally boggy moor, often away from paths. Good level of fitness required. Walk duration approx. 6-8 hours.

Please get in touch for 2023 dates
Bespoke date by arrangement
GROUP SIZE:10 persons max.
PRICE:£40 per person
MEETING PLACE:Road head at Maesnant, east of Nant y Moch reservoir (full details sent with booking confirmation)


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