Mina de Bodovalle Nature · Abanto y Ciérvana-Abanto Zierbena, Bilbo Handia / Gran Bilbao, Bizkaia Former open-pit iron mine in the Triano hills, considered the deepest mine in the Basque Country. Photo: Ebaki (CC BY-SA 4.0) What to see and do in Abanto y Ciérvana-Abanto Zierbena