Nemrut (volcano) the region. The collision of these plates began in the Middle Eocene and closed the stretch of water, which in the Mesozoic formed the Tethys Ocean. Nemrut, along with three other extinct volcanoes of eastern Turkey: Ararat, Tendürek and Süphan, is located in the area of a complex fault, which runs along the boundary of the Arabian and Eurasian plates in the territory of the Armenian Highland. It is the westernmost of these volcanoes, the only one that remains active, and generally the only volcano in Anatolia, which erupted in the historical period. Nemrut is located 10 km north of
Lake Nemrut which is in a not-eroded state. This unique structural geomorphology make it a subject of scientific research. About 450 plant species were recorded in and around Nemrut Caldera, around 200 (44%) of them belonging to the region. The diversity of the flora points out to the variation of climate conditions in the past. Around 38 (8.4%) of the existing plant species are endemic. The upside down tulip, which grows here, is a world-famous flower. The climax vegetation of Nemrut Caldera forms the haired birch ("Betula") and the trembling aspen ("Populus tremula"). Other notable plants growing around two lakes of the