Castell d'Arties is a historic castle and cultural heritage site in the charming village of Arties, located in the Aran Valley within Naut Aran, Lleida province, Catalonia. The castle, also known as Castell d'Entrasaigües, preserves medieval military architecture amid a settlement notable for its well-preserved religious and domestic monuments. Arties has earned recognition as one of Spain's most beautiful towns, featuring traditional architecture characteristic of the Pyrenean Aran Valley. Beyond the castle ruins, the village boasts other significant heritage structures including the Tower and chapel of the Casa de los Portolà dating from the sixteenth century and the historic Baths of Arties, reflecting the settlement's medieval affluence and cultural importance. The castle remains an integral part of Arties' cultural landscape, contributing to the village's appeal as a destination for visitors interested in Catalan mountain heritage and traditional stone architecture in this distinctive Pyrenean region.