This Romanesque basilica predates the cathedral and, in the opinion of many visitors, surpasses it. The church was built in the 11th and 12th centuries over an earlier structure to house the relics of Saint Isidore of Seville, brought here from Muslim-controlled Seville in 1063.
The exterior is severe and solid — this is a fortress-church. Inside, the proportions are more intimate than Gothic, and the Romanesque arches create a sense of weight and permanence. The adjacent museum holds the treasury and a remarkable collection of Romanesque art, Flemish tapestries, and manuscripts, but the highlight is the Panteón de los Reyes: twelve royal tombs beneath a ceiling covered in 12th-century frescoes that have barely faded in nine centuries.