Kõpu Lighthouse () is one of the best known symbols and tourist sights on the Estonian island of Hiiumaa. It is one of the oldest lighthouses in the world, having been in continuous use since its completion in 1531. The lighthouse is quite unique with its shape and an exception among lighthouses because it has gone through all the stages from a medieval landmark up to a modern electrified lighthouse. The lighthouse marks the Hiiu Shoal (, ) and warns ships away from the shoreline. Light from Kõpu Lighthouse can be used for navigation as far as away. Kõpu Lighthouse was previously known by its Swedish name, Övre Dagerort. Location and design The lighthouse is built at the top of the highest hillock of Hiiumaa island, Tornimägi (, ). The height of the building itself is , and the light is above sea level, making it the highest coastal light on the Baltic Sea. Kõpu Lighthouse has a shape of a square prism with massive buttresses in the directions of principal divisions of the compass. The tower is laid solely of stone up to the height of . The outside layer of the walls is supported by lime (and nowadays also cement) mortar, with the body itself built without mortar. The body of the tower contains roughly of stone, with its total weight reaching . Local limestone and glacial erratic stones were used as building material. Originally, the tower was solid stone without any rooms and no light was burned at it; when it was equipped with light, the top of the lighthouse was reached using external wooden stairs, which were later replaced with iron ones. During reconstruction in the 1800s, a stairway and two rooms were cut into the tower. Construction and history Construction of the original tower The most important east–west shipping lane in the Baltic Sea passed the Hiiu sandstone bank. Already before the year 1490 the Hanseatic merchants were seeking permission to mark this peninsula with an outstanding landmark. Around 1490 they asked the bishop of Bishopric of Ösel-Wiek to let them build a landmark on the Kõpu peninsula which was under the bishop's control. This action had no real results. At a meeting of the Hanseatic League in Lübeck in 1499, they applied once more to the bishop for permission to build a beacon. On 20 April 1500 Bishop Johannes III Orgas (John Orgies) agreed