Lake Chagan

Lake Chagan (, "Shaǵan"), or Lake Balapan, is a lake in Kazakhstan created by the Chagan nuclear test on January 15, 1965, which was conducted as part of the Soviet Union Nuclear Explosions for the National Economy program. A 140 kiloton device was placed in a hole in the dry bed of the Chagan River. The blast created a crater across and deep with a lip height of ; it is often referred to as "Atomic Lake".
The lake's water comes from the Chagan River, a tributary of the Irtysh River. The crater lake's volume is approximately . To the south, the rim of the crater holds back the waters of a second reservoir.
Media.
In Netflix's documentary series "Dark Tourist" (season 1 episode 4, "The Stans"), David Farrier visits and swims in Lake Chagan, as well as eats a fish from the lake, during his tour of Kazakhstan.