Cueva de Supelegor Nature · Orozko, Arratia-Nerbioi, Bizkaia Limestone cave in the Gorbeia massif, in the term of Orozko, linked in Basque mythology to Mari, the 'Lady of Anboto'. Photo: EGIZU Getxo Euskaldun Elkartea (CC BY 2.0) What to see and do in Orozko