A stone castle was built at Ruthin on a sandstone ridge overlooking an important crossing of the River Clwyd. The castle consisted of two wards, an upper and lower. The upper ward was the main ward of the castle and had five sides with round towers at four of the corners and a double towered gatehouse. The lower ward was rectangular in shape and had drum towers at its corners. It had its own entrance. A deep moat was dug between the two wards. In 1277 King Edward I granted the castle to Dafydd ap Gruffydd, brother of Llywelyn ap Gruffydd Prince of Wales who rebelled against the King. Dafydd and his brother had their differences and Dafydd changed his alligence several times. It was as a result of Dafydd's supporting Edward against his brother that led to him receiving Ruthin Castle from the English King. In 1282 Dafydd and his brother were reunited and attacked Edward's interests in north Wales. Dafydd was captured and executed. The castle then was granted to the Reginald, a member of the Grey family. Reginald employed Edward's master castle builder, James of St. George to make improvements at Ruthin.