San Juan de Gaztelugatxe Hermitage

San Juan de Gaztelugatxe is a tiny hermitage on a rocky islet off the Biscay coast, joined to the mainland by a stone causeway that zig-zags up 241 steps. The views of the cliffs and sea arches are spectacular, and the island found worldwide fame as Dragonstone in Game of Thrones. It's a proper hike: allow at least two hours on site, wear good shoes and expect a steep climb back up to the car park. On busy dates access needs a free timed booking online, so check before you go. From Getxo it's about 50 minutes by road — go by taxi with an agreed return time or on a ship tour.