During the Middle Ages, many fortified castles were built by feudal nobles to mark their powers. Some French castles that survived are Chinon, Château d'Angers, the massive Château de Vincennes and the so-called Cathar castles. During this era, France had been using Romanesque architecture like most of Western Europe. Some of the greatest examples of Romanesque churches in France are the Saint Sernin Basilica in Toulouse, the largest romanesque church in Europe, and the remains of the Cluny Abbey.