 There are in addition a handful of tarmacked minor public roads cut across the common, together with a number of unmetalled highways shown on Ordnance Survey maps as ‘other routes with public access’ (ORPAs).The larger part of the Begwns is formed by the Pridoli age siltstones and mudstones of the Raglan Mudstone Formation, the lowermost unit of the Old Red Sandstone (commonly reduced to 'ORS').The ORS characterises the landscape of the Brecon Beacons National Park which is seen to the south from the Begwns.