Alnwick Castle is a castle and stately home in the town of the same name in the English county of Northumberland. It is the seat of the Duke of Northumberland, built following the Norman conquest, and renovated and remodelled a number of times
Warkworth Castle, Northumberland, is a ruined medieval building. When the castle was founded is uncertain: traditionally its construction has been ascribed to Prince Henry of Scotland in the mid-12th century, but it may have been built by King Henry II of England when he took control of England's northern counties. Warkworth Castle was first documented in a charter of 1157–1164 when Henry II granted it to Roger fitz Richard.
William the Conqueror used enforced Anglo-Saxon labour for work on the construction of Leeds Castle. The original wooden castle was replaced by a fortified stone castle in 1119. An important feature of Leeds Castle is its access to the River Len. Leeds Castle occupies three islands surrounded by an artificial lake. King Henry VIII converted Leeds Castle into a Royal Palace but retained the defences due to the possible risk of invasion from Spain or France.