Fort Carré is the squat, four-pointed star fort that watches over Port Vauban from a rocky knoll just north of the harbour. It was begun in 1550 and completed by Vauban himself in the late 17th century — for two hundred years it was the southeasternmost French frontier post against Savoy. The shape, a square with four arrowhead bastions, is one of the cleanest examples of bastioned fortification on the coast.
The interior can be visited on a short guided tour. The views from the ramparts are excellent — back over the old town and across to Nice on a clear day. Allow an hour. Closed Mondays.