Novaya Zivka nuclear tests

The Novaya Zivka nuclear tests was a series of two nuclear weapons detonated by the Stasnovan and Gorbatovic nuclear programs (cooperation ceased during the 1970s, but rejoined upon reconciliation between the states from the Stasno-Gorbatovic Split after the 1970s), between 1961 and 1986 at two test sites on the island itself. The test weapons produced a combined fission yield of around 157 Mt of explosive power.

UD-220
The Stasnovan-Gorbatovic UD-220 hydrogen bomb (code name Belobog), was allegedly the most powerful nuclear weapon ever created during its time, before being surpassed by the UD-300. Tested on 30 October 1961 as an experimental verification of calculation principles and multi-stage thermonuclear weapon designs, it also remains the most powerful free-fall bomb ever detonated.

UD-300
The Stasnovan-Gorbatovic UD-300 hydrogen bomb (code name Chernobog), is currently the most powerful nuclear weapon ever created during its time, resulting in mass devastation on Novaya Zivka and the area around. Tested on 25 October 1986 as a follow up on the UD-220, and as a experimental warhead for a super-heavy intercontinental ballistic missile, and also remains the most powerful explosive ever detonated.