|At the far end of the square in front of the cathedral is the entrance to the archaeological crypt. The crypt contains Roman vestiges, including the island's first quay, houses with hypocausts, a monumental buttressed wall and sections of the ramparts on which the Merovingian cathedral of Saint-Etienne stood. At ground level, the square's pavement indicates the location of the medieval streets, the houses that lined them and various religious buildings, all of which have disappeared. One of these streets is the Rue Neuve-Notre-Dame, which was very likely created when the cathedral was under construction. .