Castrojeriz

Founded as a pilgrim hospital by Alfonso VII in 1146, San Antón was entrusted to the Antonines, an order known for caring for sufferers of "St Anthony's fire", now understood as ergot poisoning caused by fungus-contaminated rye. Most of the surviving ruins date from the 14^th century, but the raised portico whose two arches span the Camino was added in the early 16^th century. Two small recesses in the walls were once used to leave food for pilgrims who arrived after the gates had closed. Since 2002, the tradition of hospitality has been revived in the ruins at the Hospital de Peregrinos San Antón.

The castle of Castrojeriz was rebuilt as a frontier stronghold in the late 9^th century and continued to be expanded throughout the Middle Ages. It witnessed repeated struggles for control of the region and in 1359 was the scene of the imprisonment and execution of Eleanor of Castile, Queen of Aragon, on the orders of her nephew Pedro I of Castile. Although much of the fortress is now ruined, the climb offers extensive views over Castrojeriz and the surrounding Meseta.

Construction of the former collegiate church of Santa María del Manzano ("Our Lady of the Apple Tree") began in the early 13^th century under the patronage of Queen Berenguela of Castile. It houses the 13^th-century stone image of the Virgen del Manzano, whose reputed miracles were celebrated by Alfonso X the Wise in several of his Cantigas de Santa María. The church also preserves the damaged Gothic tomb of Eleanor of Castile, Queen of Aragon.

The Iglesia de San Juan reflects the prosperity of Castrojeriz's merchant families, many of whom traded Castilian wool with Flanders and chose the church for their family tombs. Its Gothic cloister preserves three galleries with paired columns, pointed arches and a late 15^th-century Mudéjar wooden ceiling. Inside, a collection of Flemish tapestries reflects the town's long commercial and artistic connections with the Low Countries.