Patmos is located in the northwest end of the Dodecanese, between Ikaria and Leros. Patmos is of volcanic origin and has a much indented coastline. An isthmus only a few hundred meters wide, on which the island's harbor lies, separates the north end of the island from the southern half, with the famous monastery of St.John, who wrote the Book of Revelation here in the later part of 1st century AD. Many believe that is the most impressive island in terms of natural beauty. The tourist infrastructure, the healthy mild climate, the pure atmosphere, the laced shores, the very beautiful gulfs, the crystal clear sea, the surrounding islets and the sites, promise unforgettable vacations.