The Abbey of Saint Maurice, Agaunum ( or Saint-Maurice-en-Valais) is a Swiss monastery of canons regular in Saint-Maurice, Canton of Valais, which dates from the 6th century. It is situated against a cliff in a section of the road between Geneva and the Simplon Pass (to northern Italy). The abbey itself is a territorial abbacy and not part of any diocese. It is best known for its connection to the martyrdom of the Theban Legion, its original practice of perpetual psalmody, and a collection of art and antiquity.