This lighthouse was manufactured in 1923. The altitude of tower is 9 metres and the height of focal plane is 23 metres. The access in the lighthouse becomes with boat from Spetses Island. The islet of Dokos, Hydra Island Dokos (meaning "beam" in Greek) is a small islet in the Saronicos - Argolicos bay, situated between Hydra and the opposite coast of Ermioni at the Peloponnese, close enough to Spetses. The island is mountainous and pretty rocky, with the higher altitude to reach the 308 meters. It is a barren island with scarce water sources. Today it counts some 50 permanent residents occupied in stockbreeding and fishing, but it receives many visitors, mainly naturists who come here to enjoy free camping at the northern coasts of the island, or to visit the women's monastery of Aghia Eupraxia. According to the archaeological finds, the island seems to have been populated as early as in the late 5th millennium b.C. (Late Neolithic period), but it flourished a bit later, during the Early Helladic period in the 3rd millennium b.C., thanks to the rapid development of navigation. During the Mycenaean times there had been established and developed the settlements at the sites of "Ledeza" and "Kommeni Myte". From the Archaic times and throughout antiquity the island was called Aperopia. Throughout its history the island was a strategic point of great importance, a fact well confirmed by the ruins of the Byzantine castle which was also used and extended by the Venetian. The location of the island allowed to whoever dominated it to control the marine transports of the Argolicos bay up to Eastern Laconia. During the Greek Revolution of 1821 the fleet of Hydra used the islet as a safe port for winter. In 1970s' it has been found in the area around Dokos the most ancient shipwreck of the world, dated in the second half of the third millennium b.c.