St. Domingo descendant of the galician family of the Counts of Traba, founded it when he visited Santiago in 1220. The church, from the 14th century, was built according to the standards of mendicant architecture; simple, though monumental, in appearance, with an impressive sanctuary. It has a Latin-cross ground plan, with three aisles, transept and polygonal apses. In the partico arch, there are three Romanesque images. The central apse houses the Gothic tombs of the Altamira family, and to the left of the central aisle, the Pantheon of Illustrious Galicians. In the monastery building, from thre Baroque period, it is worth noticing the triple-ramp spiral staircase, designed by the architect Domingo de Andrade. He also took part in the church and convent facades, the cloister and the monastic buildings. The cloister has nine sections of each side, with semi-circular arches and a rectangular frame. The typical decoration of Compostela baroque can be seen on the pillars, mainly garlands of fruit. Currently, the convent is the headquarters of the Galician People´s Museum, and the local council has devoted the church area to setting up temporary exhibitions. The building has been a Historical-Artistic Monument since 1912.