The photo has been mistakenly credited as the Soviet test Joe 1 (Richard Rhode's 1995 Dark Sun: The Making of the Hydrogen Bomb and David Holloway's 1994 Stalin and the Bomb).
The site was a dry bed of the Chagan River at the edge of the Semipalatinsk Test Site, and was chosen such that the lip of the crater would dam the river during its high spring flow. The resultant crater has a diameter of 408 meters (1,338 feet) and is 100 meters (328 feet) deep.
Lake Chagan (or Lake Balapan), Kazakhstan, is a lake created by the Chagan nuclear test. It is roughly 10,000,000 m3 in volume, or 2.6 billion gallons. It is located at the co-ordinates: 49.935091 N,79.010754 E.
As of 2008, the area is still radioactive, and has been called the "Atomic Lake". As at the Trinity site of the first United States nuclear weapon test in Alamogordo, New Mexico, the exposed rock was melted into a glassy substance.