Castañoso hillfort and sauna Nature · A Fonsagrada, Fonsagrada, Lugo A fortified settlement of some two thousand years ago that holds the best-preserved hillfort sauna in the north-west of the peninsula: a 1st-century building with several rooms, a corbelled dome and some 120 square metres, excavated since 2015. Photo: Nemigo (CC0) What to see and do in A Fonsagrada