The transfer of the episcopal see of Auca Historical milestone · Villafranca Montes de Oca, Montes de Oca, Burgos Image of Villafranca Montes de Oca, not of the place itself. The ancient city and episcopal see of Auca occupied this site. In 1075 Alfonso VI moved the bishop's chair definitively to Burgos and the bishopric of Oca disappeared, leaving the villa reduced to a stage of the Camino. 1075 Photo: Jialxv (CC BY-SA 4.0) What to see and do in Villafranca Montes de Oca