Gaztelugatxe is an islet on the coast of Biscay, only 35kms from Bilbao. It is connected to the mainland by a 241-step dragon-ridge-shaped bridge, used to be the filming location of "Dragonstone" in the American series “Game of Thrones” Today, it has become a tourist attraction. The visit of Gaztelugatxe is free, but the number of daily visitors is limited, and online reservations are required in advance.