Disco Demolition Night was a event that took place on July 12, 1979 in Chicago, set up by notorious DJ Steve Dahl. The aim was for disco-haters to bring the records they no longer wanted and for them to be blown up with a small bomb.
Prior to this Steve created a pretend group called "The Insane Coho Lips Anti-Disco Army", part of his campaign against disco promoted on his radio show.
The Disco Demolition Night was planned to occur during a break in a baseball game but eventually lead to a riot
75,000 extra people turned up to the game to participate in the demolition; way more than the baseball park could cope with. They all brought crates of records, throwing them like frisbees at the baseball fans during the game.
When the bomb was finally exploded it tore a hole in the field. Thousands rushed onto the grass, lighting other fires, stealing the bases, ripping up more grass, etc.
Eventually riot police were called in.
According to the 1986 book "Rock of Ages: The Rolling Stone history of Rock and Roll" the event was the "emblematic moment" of the anti-disco "crusade" and noted that "the following year disco had peaked as a commercial blockbuster".