Promontory fort

A promontory fort is a defensive structure located above a steep cliff, often only connected to the mainland by a small neck of land, thus using the topography to reduce the ramparts needed.

Others, like Dalkey Island (County Dublin) contain imported Eastern Mediterranean pottery and have been reoccupied and changed in the early medieval period.

All have a rampart on their vulnerable landward side, and excavations at Cronk ny Merriu have shown that access to the fort was via a strongly built gate.

The Scandinavians who arrived in Mann in the eighth and ninth centuries AD sometimes re-used these Iron Age promontory forts, often obliterating the old domestic quarters with their characteristic rectangular houses; the fine example at Cronk ny Merriu has been used as the basis of the reconstruction in the House of Manannan museum in Peel.

The famous site at Tintagel may be a rare example of promontory fort whose occupation continued into the post Roman and from there into later periods.