Lake Nemrut the world. Nemrut Caldera is world's second largest one. The western half of the crater is covered by the lake. AT the summit, there are five lakes, two of them existing permanently and the others seasonal. The biggest of the lakes is Lake Nemrut in the form of crescent. It contains freshwater of colorless, odorless and drink water quality. Lake Nemrut is situated at an elevation of about above main sea level. It has an area of , and its average depth is about with a maximum depth of . Nemrut Caldera is on the youngest volcanic cone in Turkey,
Nemrut (volcano) the city Tatvan, in the north-western shore of Lake Van. Nemrut was probably formed in the early Quaternary Period, about 1 million years ago. It showed the greatest activity in the Pleistocene, with regular eruptions occurring in the Holocene. In the middle Pleistocene, about 250,000 years ago, a major eruption formed a lava flow over 60 km long, which blocked the water discharge from the Van basin and formed Lake Van, the world's largest alkali endorheic lake. In the same period, the conical top of the volcano collapsed inward, forming an 8.3×7 km caldera. Later, the freshwater Lake Nemrut formed