On April 26, 1986, the Chernobyl nuclear reactor melted down, but the rest of the world wouldn't learn how close it came to nuclear Armageddon until weeks later.

Sunday, April 26, marks the 40th anniversary of the world’s worst nuclear power plant accident at the Chernobyl nuclear power station in the Soviet Union.

These 20 pictures capture the aftermath of the infamous 1986 Chernobyl incident—effects that are, in some cases, still felt today.

The two explosions at the Chernobyl nuclear power plant came decades apart.

Once classified files from East Germany reveal the extent of Soviet actions to hide the true extent of catastrophe.

The nuclear incident at Chernobyl spread radiation across Europe and led to political changes that played a role in the collapse of the Soviet Union.

April 26 marks the 40th anniversary of the explosion at Reactor 4 of the Chernobyl nuclear power plant in Ukraine. The accident caused the largest ever release of radioactive material into the environment,

Across the Chernobyl exclusion zone, Przewalski’s horses — stocky, sand-colored and almost toy-like in appearance — graze in a radioactive landscape larger than Luxembourg.

Chicago Electronic Artist Turns Historical Obsession Into Music — and a Mission to Aid Displaced Ukrainians Forty

In the novel "When There Are Wolves Again" by E.J. Swift, the Chernobyl disaster and its legacy is extrapolated to a near future where natural habitats are depleted and precarious.

Photos of the infamous nuclear Chernobyl site show the abandoned power plant frozen in time — with a control panel still lit up ahead of the 40th anniversary of the unprecedented disaster.