This church still includes Romanesque elements such as the tower and the north cloister, which is of the 13th century. There is no doubt that the tower stands out among the monuments of the city and has become its symbol. It is located at the foot of the church and access is from inside. The arches are decorated with nail tips. The tower retains its roof in the shape of a pyramid with its tiles in the form of scales, as the distant model for this tower is from Lombardy. The cloister is related to that of Las Huelgas de Burgos; it is on the north side of the building as it constituted a viewpoint over the branch of the River Esgueva which formerly flowed below it. In the 14th century the main section of the Romanesque building was demolished to leave only the tower and the portico.