Castle of Castelltallat (Isona) Monument · Isona i Conca Dellà, Pallars Jussà, Lleida 11th-century Romanesque fortress, with tall walls and rectangular structures, among them a possible tower and a vaulted chamber; today in ruins, with wall fragments whose plan cannot be made out without archaeological excavation. It belonged to the former municipality of Conques, was probably conquered by Arnau Mir de Tost, and served as a bailiwick castle; in the 14th century it passed to the barony of Orcau, and in the 20th century it became a farmhouse. A Bien Cultural de Interés Nacional (Catalonia's top heritage-protection category) (there is another of the same name in Sant Mateu de Bages, which should not be confused with this one). Photo: Gustau Erill i Pinyot (CC BY-SA 3.0) What to see and do in Isona i Conca Dellà