Les Catacombes. A 2 hour queue but unique and extremely macabre. After descending 21 metres down a narrow spiral staircase, you wander through a long abandoned quarry tunnel, which eventually leads to the ossuary filled with the bones of people moved there when the cemeteries became full. The walls are lined with leg bones and skulls arranged in rows. Allegedly the bones of Jean-Baptiste Lully are there somewhere but there could be no way to identify them among the thousands of other skeletons.