Dalveen Pass is the most southerly and the longest pass within the Lowther Hills. It runs from Carronbridge on the A76 just north of Thornhill to Elvanfoot near the M74 and carries the A702 trunk road. The road passes near the village of Durisdeer en route and reaches a height of 350 metres at the top of the pass. It is the only pass enlarged by ice into a U-shaped glacial trough, hence the road has to climb up the steep side to gain the head.