Declassified footage of most powerful nuclear bomb ever detonated was kept top secret for decades

The world's largest nuclear explosion ever took place in 1961, but it wasn't until almost 60 years later that footage was released of the huge blast.

It was in the midst of another global issue that Russia declassified footage of the 'Tsar Bomba', or the 'Tsar Bomb' - while humanity was dealing with lockdowns caused by the coronavirus outbreak in August 2020.

See the blast take place below:

Needless to say, the release of the video marked a stark change from the endless episodes of Friends and obsession withTiger King that most people were in to at the time.

Shared by Russian state nuclear agency Rosatom, the video was released for the first time as part of a documentary marking the 75th anniversary of Russia's atomic industry.

Dubbed the 'King of Bombs', the Tsar Bomb was developed between 1956 and 1961, while the Soviet Union was in the middle of an nuclear arms race with the US.

It was said to be 3,300 times as destructive as the bomb that devastated Hiroshima, made up of a hydrogen bomb with 50 megatons - or 50 million tons - of explosives.

The mushroom cloud was higher than Mount Everest (Росатом)

When it was tested in October 1961, the Tsar Bomb released a mushroom cloud that was 60km high.

Cameras stationed on the ground and on board two Russian aircraft caught the moment the bomb caused a huge fireball in the sky.

The documentary which featured the footage opened with the words 'Top Secret' and offered insight to every stage of the test, from the transportation of the bomb, which weighed 27 tonnes and was about eight metres in length, to the measurements taken in the aftermath of the explosion.

Over the footage, a narrator said: "The testing of an exceptionally powerful hydrogen load ... confirmed that the Soviet Union is in possession of a thermo-nuclear weapon with power of 50 megatons, 100 megatons and more."

Cameras on aircraft caught footage of the blast (Росатом)

When it went off, the explosion of the Tsar Bomb was so powerful that the shockwave could be felt from about 70 miles away, with the blast itself visible from an incredible 620 miles.

The Tsar Bomb was one of a number of detonations Russia carried out during the arms race, but the 'King of Bombs' was one of the last above ground nuclear tests ever carried out.

When the US, UK, and the Soviet Union signed the Partial Test Ban Treaty in 1963, it was agreed that all future tests had to be carried out below the ground.