Barrage Vauban

This seventeenth-century defensive weir spans the Ill river at the edge of the historic centre, designed by the celebrated military engineer whose name it bears. Its arched stone gallery could be used to flood the southern approaches to the city in the event of a siege. Restored as a covered walkway, it now displays casts of cathedral sculptures and offers a panoramic rooftop terrace. From the top, visitors gain a classic view over the covered bridges and half-timbered houses of the Petite France quarter.