 During the English Civil War, Plymouth declared for Parliament and was besieged in 1643 by Royalist forces; the castle was again made ready for defence but saw no action.The castle was later used as a prison, then as a workhouse and finally as a source of building material for the expanding town.A small section of the castle fabric survives in the Barbican area of Plymouth, located in Lambhay Street, at the head of a flight of stairs leading down to the Mayflower Steps on the quayside.