Aonghasa

Aonghasa, also known as Dún Aonghasa, is a prehistoric hill fort located on Inishmore, the largest of the Aran Islands off County Galway, Ireland. It sits on a prominent promontory overlooking the Atlantic, with sea cliffs forming a natural defense on multiple sides. The site is one of the best-known examples of ancient fortifications in Ireland and is a major element of the Aran Islands’ landscape and heritage.

Dating and purpose: Dún Aonghasa is generally dated to the late Bronze Age and early Iron Age, with construction and modifications occurring from roughly the first millennium BCE into the first centuries CE. The fort comprises concentric lines of stone ramparts that enclose a central area, forming a multi-ring defensive complex. The exact sequence of building phases is not fully established, but the layout reflects long-term use as a defensive, ceremonial, and residential site within the wider Irish prehistoric tradition.

Layout and features: The fort’s defenses are built of heavy dry-stone masonry, adapting to the rocky promontory. The outer wall forms a circular to oval enclosure that protects an inner court and any traces of dwelling spaces or other structures remain inconspicuous due to centuries of weathering. Access is via a narrow entrance in the outer rampart, with the surrounding cliffs providing natural fortification.

Protection and access: Dún Aonghasa is designated as a National Monument of Ireland and is a key part of the cultural heritage of the Aran Islands. It is accessible to visitors by footpaths from nearby villages, with careful stewardship to preserve the site’s integrity. The fort continues to be a focus of study and tourism, reflecting Ireland’s prehistoric past.