Dún Aonghasa Fort

Dún Aonghasa is a prehistoric stone fort located on the island of Inis Mór, the largest of the Aran Islands off the coast of County Galway. The fort is perched on a limestone cliff rising 87–100 metres above the Atlantic Ocean, forming a semi-circular enclosure that opens toward the sea. Massive dry-stone walls, up to 6 metres thick in places, define the structure, while a series of defensive lines extend inland. One of its most striking features is the chevaux-de-frise, a dense field of upright stone slabs placed outside the walls to deter attackers. The surrounding landscape is characterised by exposed limestone pavement, low vegetation, and expansive ocean views, making the site both visually and archaeologically distinctive.