The Horseshoe Pass (Pass of the Cold Stream) is a mountain pass in Denbighshire, northeast Wales. It separates Llantysilio Mountain to the west from Cyrn-y-Brain to the east. The A542 road from Llandegla to Llangollen runs through the pass, reaching a maximum height of 417 metres (1,368 ft). The road travels in a horseshoe shape around the sides of a valley, giving the pass its English name; this route dates from 1811, when a turnpike road was constructed across the area. The road is frequently closed in winter due to snowfall or landslides.