Built in 1921, on a site that was chosen by Marshal Foch to commemorate the two Battles of the Marne, this memorial is a grouping comprising a crypt, a big chapel enhanced with exceptional stained-glass windows and a cloister leading to an ossuary which contains the remains of 1,500 unknown soldiers. By
climbing a staircase with a hundred or so stairs, visitors will have access to a rampart walk offering them an unobstructed view of
the entire Valley of the Marne River.