Volunteers have joined experts in learning more about an Iron Age settlement on the north Wales coast before it washes into the sea.

Archaeological digs at the coastal fort near Dinas Dinlle have uncovered a huge Iron Age roundhouse, thought to be 2,500 years old, as well as Roman pottery.

Volunteers and experts have been on site this summer to find out more about the little-known Dinas Dinlle National Trust-owned monument in Gwynedd before it falls into the sea.

The 43ft (13m) wide roundhouse was buried by coastal sand, thought to have blown there during a sandstorm in 1330.

Coins found at the fort suggest it was occupied in Roman times.

The “well-preserved” roundhouse - with its 8ft thick walls - was uncovered (see photo) close to the cliff edge buried underneath 3ft of sand during a two-week dig.

“It’s probably the biggest one I’ve ever seen in 30 years of archaeology,” said David Hopewell, senior archaeologist at the dig.

“In another trench we have another big wall which may be another roundhouse but we’re not entirely sure yet.

“The main problem is that everything is under a metre of sand and we’re wondering if it blew in the big storm in 1330 - so it looks like it’s been buried for a long time and it’s superbly preserved.”

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