Northburg Castle is locally known as ‘Greencastle’ and was one of the most impressive Norman castles built in Ireland. It was built by Richard de Burgh: The Red Earl of Ulster in 1305 on a promontory rock overlooking Lough Foyle. The castle was built using the finest materials and latest building techniques by the best craftsmen. The walls in the polygonal tower are over 12-feet thick! It was attacked and captured by Robert the Bruce of Scotland soon after its completion in 1316. Robert crowned himself ‘King of Ireland’ but the castle was soon after recaptured by De Burgh again. In 1333 his grandson, William, was murdered here in revenge for slowly starving his distant cousin, Walter de Burgh to death! This was the point that really ended Norman power in the North West. The castle later fell into the hands of the powerful O’Doherty Clan of Inishowen. In 1555 the O’Donnell’s attacked the O’Dohertys here using cannon and nearly destroyed the complete structure.