At 280mm, the Atomic Cannon was the largest nuclear-capable mobile artillery unit ever produced by the United States.
This footage from the 1953 'Grable' test shows the cannon firing an atomic projectile in the Nevada desert. The bomb exploded with a force of 15 kilotons, roughly equivalent to the nuclear blast at Hiroshima. The footage was bumped up from its original 24fps resolution to 4k 48fps using neural networks.
If you thought that was cool, check out this footage of NYC in 1911
that was also enhanced using neural networks.