At the time Prestatyn Castle was built in 1157 there was a thriving community in Prestatyn which included fishing boats, market place, mill, blacksmith's shop and a granary. Some of its inhabitants put out to sea in small sailing boats, returning home with fish. Their boats were kept in a harbour nearby on Prestatyn Gutter.

To find the castle ruins stand on Bodnant Railway Bridge, Prestatyn Road, and look into the field on the left (with your back to the sea) where you will see a stone pillar on top of a raised mound.

The castle's history was brief, spanning a mere 10 years. The Welsh Prince Owain Gwynedd razed both the castle and the surrounding Norman town to the ground in around 1167, although it is said that part of the castle was still standing in 1297.

The castle consisted of a wooden tower standing on a motte (mound) of about 20m in diameter, surrounded by a ditch and defended by a bailey (outer defensive wall), probably made of wooden stakes sharpened at the top.

King Henry II charged Robert Banastre (born in 1130 in Prestatyn) with building Prestatyn Castle and he enlarged the township.

Henry's quarrel with Thomas Becket, Archbishop of Canterbury, distracted his attention from Wales and the Welsh united under the leadership of Owain Gwynedd and regained territory they had earlier lost to Henry.

Prestatyn's strategic Norman garrison faced the approaching Welsh armies under Owain Gwynedd. The battle was soon over, the garrison overwhelmed, proving no match for Owain Gwynedd's army who destroyed the castle so that it would no longer stand guard on this coastal route.