Castle of Lorca Monument · Lorca, Alto Guadalentín, Murcia A fortress from the 9th to the 15th centuries covering 52,000 square metres with 1,426 metres of walls, one of the largest in Spain; it went from being an Islamic stronghold to a Christian bastion after the conquest by Alfonso X in 1244. It stretches 640 metres in length by about 120 at its widest point, making it one of the largest castles in Spain, and it was a key stronghold in the conflicts between Christians and Muslims on the frontier of the Kingdom of Granada. It is listed as a Bien de Interés Cultural (Spain's highest level of heritage protection) and forms part of the delimitation of the historic-artistic ensemble of Lorca. Photo: Jose Lorca (Public domain) What to see and do in Lorca