Dinas Dinlle Iron Age Hill fort

This coastal Iron Age hill fort in the community of Llandwrog was built on an isolated hill of glacial drift known as Boncan Dinas, but it has now been considerably eroded by the Irish Sea and the feet of tourists. There is a popular award winning beach on the foreshore, providing views of the Northern coast of the Lleyn Peninsula and Llanddwyn Island, Anglesey. A Second World War seagull trench (due to its shape, spread seagull wings) has been built into the lower northern rampart, which is in good condition. The hill fort is close to Caernarfon airport, which was a RAF base at that time. It’s interesting that modern defences have been constructed and incorporated with ancient defences, which goes to prove the strategic importance of the location.

The hill fort was oval in shape, and was defended by a double bank, (two earthen ramparts) having an entrance to the south-east. The interior of the fort contained some circular buildings, and possibly a burial chamber and a Roman lighthouse (pharos) was once at the fort. The site has not been fully excavated, but there have been shards of Roman pottery found in the past which suggests a Roman reoccupation of the defences in the 2nd and 3rd Centuries.

Dinas Dinlle is thought to be Dinas Dinllev from the ‘The Mabinogion’ tale ‘Math The Son Of Mathonwy‘ Lady Charlotte Guest (1877).