The government of Turkey has named as its 14th Wetland of International Importance the Nemrut Caldera (Nemrut Kalderasi) (4,589 hectares, 38°37’10”N 042°13’54”E), the caldera of the Nemrut volcano located on the western shore of Lake Van in the eastern part of Turkey (Eastern Anatolia) and one of the most important wetlands of Bitlis province. With its structural morphology that is unique in Turkey, the site qualifies for the Ramsar List under Criterion 1 on "representative, rare, or unique examples of a natural or near-natural wetland type found within the appropriate biogeographic region".
As summarized by Ramsar’s Laura Máiz-Tomé from the accompanying information, the eastern half of the caldera is filled by pyroclastic deposits related to maar-like explosion craters, lava domes and flows. The western half is filled by a freshwater lake and a small lake with hot springs, in addition to a number of small temporal lakes. The largest lake, Lake Nemrut, has a half-moon shape, an average depth of 100 meters, and colorless, odorless and drinkable water.
There are rich plant communities in the caldera and Velvet Scoter Melanitta fusca used to breed in Nemrut in 1989. The site is government-owned, but some livestock grazing takes place. The main activities are recreation and tourism, and there is a winter sports and ski centre in the surrounding area. The main ecological threat to the site is overgrazing.