Ewloe Castle is a mid 13th century stone keep and courtyard fortress, founded by Prince Llewellyn ap Gruffydd. Built around 1257, there is no known history of this typically Welsh castle, which is thought to have been abandoned after King Edward I invasion of Wales in 1277.
On a narrow ridge, against the steep slope formed by the valley of the Wepre Brook, the upper ward stands on a scarped and revetted knoll.
Set within an irregular walled enclosure, with its southern half standing to the original height, is a characteristic two storey apsidal-ended keep and the steps of its forebuilding.
To the west, the lower walled enclosure with its well and a large circular two storey tower, abuts to the upper ward but there is no obvious access between the two.
Defended from the south, by a deep rock-cut ditch, with a substantial counterscarp bank, the castle is shielded by a great rampart on the lip of the valley above.