Bausen is situated in the northwestern part of the region, bordering the Occitan region of Comminges. It is a very mountainous municipality, composed mainly of granite rocks and Silurian outcrops, and is drained by the Bausen river. In the highest areas, such as the Vacanera mountain range, mountain lakes like Era Cigalera are found.
The municipal area features important fir and beech forests, notably in the Saplau area, and is part of several natural parks. The village is connected to the Vielha road by a forest track. Historically, in medieval documents, the municipality was known as Balsen or Bolson and belonged to the terçon of Es Quatre Lòcs.
The presence of a fragment of a Roman marble cinerary stele in the Church of Sant Peïr ad Vincula underscores the long history of settlements in the area.
One of the most prominent architectural elements is the Church of Sant Peïr ad Vincula, a modern building dating from the beginning of the 18th century. The voussoir of the Renaissance door, which bears the date 1709, is one of the most notable features. Inside, the nave is covered with a barrel vault, and to the left of the entrance door, a fragment of a Roman marble cinerary stele with three busts is embedded.
Bausen is located 24.7 km from Vielha e Mijaran (the regional capital) and 185 km from Lleida (the provincial capital).
