De Concordia Julia Nertobriga a la reconquista cristiana Historical milestone · Cumbres de San Bartolomé, Sierra de Huelva, Huelva The municipality arose from the decline of Concordia Julia Nertobriga, an ancient Roman-Celtic city. As a border stronghold, it was reconquered from Muslim rule in the mid-thirteenth century and incorporated into Christian Castile. Photo: Estevoaei (CC BY-SA 4.0) What to see and do in Cumbres de San Bartolomé