Founded before 1144 by regular canons linked to the Abbey of Abondance, Sixt Abbey anchors the village and is the oldest substantial building in the valley. The Church of Saint Madeleine still stands, its 13th-century Gothic choir with ribbed vaults largely intact; the conventual buildings behind it house former refectories and the canons' cells. Medieval artefacts and early modern religious objects are displayed in the sacristy.
The abbey survived until the French Revolution, when the canons were dispersed in 1792 and the buildings were repurposed as an inn. Restoration began in earnest after 2010 when archaeological investigations uncovered Romanesque cloister foundations, medieval burial sites, and building phases spanning eight centuries. Visits are possible when the church is open; check locally for times.