Castle of el Bailío de Caspe Monument · Caspe, Bajo Aragón-Caspe, Zaragoza Remains of the medieval castle of the Bailío de Caspe, next to the Colegiata de Santa María la Mayor, with which it formed a kind of mixed acropolis of religious, civil and defensive buildings that also included a convent of the Order of Saint John. The castle was the residence of the commanders of that military order. Photo: Anonymous (Public domain) What to see and do in Caspe