Warsaw radio mast

The Warsaw radio mast was the tallest structure in the world from 1974 to 1991, reaching 647 meters (2,120 feet). It was located in Konstantynow, Poland. It was designed by Jan Polak.

On August 10, 1991, it collapsed during renovation work. Three people were killed and 12 injured when it came down.

With its collapse, the KTHI-TV television tower outside of Fargo, North Dakota, USA, became again the world's tallest structure, standing at 629 meters (2,063 feet) tall.