The commune of Saint-Aventin is located in the heart of the Pyrenees, and extends from the Larboust Valley in the north to the Spanish border in the South.

The municipal territory hosts the Luchon-Superbagnères winter sports facilities, accessible only from Bagnères-de-Luchon by road or Cable car.

The population density is 5.3per/km² The Romanesque Church Saint-Aventin dates from the 11th or 12th century, has two bell towers, a porch decorated with sculptures, and capitals showing scenes of the life and martyrdom of saint Aventin.

The exterior walls have incorporated stone from previous buildings that reuse of stelae and pagan altars dedicated to Pyrenean gods, including Abellio and Aherbelst.

Inside the church are monumental paintings, a baptismal font and a wrought iron altar.