The Brouage Ramparts, built between 1630 and 1640, are an excellent example of the art of fortifications before Vauban. Forming a square with sides 400m long, they are protected by seven bastions equipped with bartizans. The North side faced the sea, giving onto a harbour that is now merely a channel. You can stroll across almost their entire length on the grassy wall-walk. The layout of the fortress can be seen quite clearly, while the view extends over the marshes and the islands of Aix and Oléron.