Beyşehir (pronounced [ˈbejʃeˌhiɾ]) is a municipality and district of Konya Province, Turkey. Its area is 2,054 km, and its population is 77,690 (2022). The town is located on the southeastern shore of Lake Beyşehir and is marked to the west and the southwest by the steep lines and forests of the Taurus Mountains, while a fertile plain, an extension of the lake area, extends in the southeastern direction.
Lake Beyşehir (Turkish: Beyşehir Gölü; anciently, Carallis or Karallis (Ancient Greek: Κάραλλις), or Caralis or Karalis (Κάραλις)) is a large freshwater lake in Isparta and Konya provinces in southwestern Turkey. It is located at around 37°47′0″N 31°33′0″E / 37.78333°N 31.55000°E and is the largest freshwater lake in Turkey. It has an area of 650 km and is 45 km long and 20 km wide. It carries the same name as the principal urban centre of its region, Beyşehir. Anciently, it was considered part of ancient Isauria.
The lake is fed by streams flowing from the Sultan Mountains and the Anamas Mountains. The water level in the lake often fluctuates by year and by season. Lake Beyşehir is used for irrigation and aquaculture, although it is also a national park. There are thirty-two islets in varying sizes in the lake. Lake Beyşehir is also an important site for many bird species.