The ossuary, the most important French monument commemorating the Great War of 1914-18, was built to receive the remains of some 130 000 unidentified French and German soldiers killed during the Battle of Verdun. This vast 137m-long necropolis, with its 18 bays each containing two granite sarcophagi, is crowned by the 46m-high Tour des Morts, on the first floor of which is a small war museum. In front of the ossuary stand the 15 000 crosses of the National Cemetery.