Bull Rock Lighthouse

The Bull Rock Lighthouse, is an active navigational aid located on Bull Rock, 4 km off Dursey Island, Ireland. Bull Rock is unique in that a hole passes all the way through it. Irish mythology claims the rock as Tech Duinn, the "house of Donn", where the souls of the dead gather. The hole became known as the "Entrance of the Underworld". The rock is uninhabited and cannot be directly visited, but only by boat tours around the rock.