Dunbeg is a small promontory fort dug into a cliff edge above the Atlantic, about 8 km west of Dingle on the Slea Head Drive. Built over several phases between the 6th and 11th centuries, the fort consists of an earthen rampart, a stone wall pierced by a tunnel-like passage, and a single drystone clochán (beehive hut) inside. The site is small enough to walk round in twenty minutes and dramatic enough to be on every coach itinerary.
The cliff is actively eroding — a large section collapsed in winter storms in 2014 and 2018 — and the site is occasionally closed for safety. The visitor centre across the road runs short tours, charges a small fee, and serves a respectable bowl of soup. The Iron Age site of Fahan, with its dense cluster of beehive huts, is a few kilometres further west and is the better stop if you want to see clocháns properly.