Near Barbastro we find one of the best monumental ensembles in Aragon, built around a rock where the Castle and the Collegiate Church stand. The Collegiate Church, consecrated in the 11th C., keeps only part of the original structure. The old Romanesque porch was used to build the current cloister, where some interesting carved capitals are conserved.
The castle (11th C.) conserves part of the walls, the watch-tower, part of a tower and rests of the church of Santa Maria Magdalena. There is a guide service in the mornings and afternoons.