The Colosseum had a retractable roof, operated by a crew of sailors, almost 2000 years before any modern stadium.
— James Lucas (@JamesLucasIT) May 24, 2026
It was called the velarium: an enormous awning of canvas and rope that could be drawn across the open top of the arena to shade fifty thousand spectators from the… pic.twitter.com/51pK91G2W7
