Cairn na Burgh Mòr is the larger of the two "Carnburgs" (as they are nicknamed) at the northeastern end of the Treshnish Isles in the Inner Hebrides - the other being "Cairn na Burgh Beag". The larger of a pair guards the entrance to Loch Tuath on the west coast of Mull. These grassy islands are both remnants of ancient lava flows, and have a distinctive profile: flat-topped and trimmed with cliffs. Cairn na Burgh Mòr has fortifications on the grassy slope. Cairnburgh Castle and a chapel are located on the isle.