Castell de Sant Ferran was built in the mid 18th Century to defend the border with France. This impressive fortress was one of the most extensive in Europe, and had a huge parade ground. French forces captured the castle during the Napoleonic Wars, and it has served as a training ground and a prison. The fortress is now open to visitors and the vaulted stables should not be missed. Jeep tours of the ramparts are available as well as dinghy trips of the underground cisterns.
