Lake Sapanca is a fresh water lake in Turkey, between the Gulf of İzmit and the Adapazarı Meadow. The lake has a catchment area of 251 km², surface area is 45 km², a length 16 km east-west / 5 km north-south, and a maximum depth of 52 m.
Sapanca Lake is located on a tectonic hole, which is situated between Izmit Bay and Adapazari Meadow and runs parallel to Iznik Lake.
The catchment area of Lake Sapanca – about 251 km2 – is surrounded by mountains in the south and small hills in the north. Water is taken from the Lake for domestic and industrial needs.
The region around Sapanca has become a destination for day trips and weekend vacations