Today, the world’s largest stadium/arena is Narendra Modi Stadium, which holds 132,000 spectators. But that’s a far cry from the largest one ever built. For that, you have to go back to ancient Rome’s Circus Maximus.
The Circus Maximus was a chariot racing stadium and the largest stadium in the entire Roman Empire. To this day, no one has ever built a bigger enclosed stadium.
Built in the 7th or 6th century BCE, it was also used for festivals and other competitions. It was big enough to hold wild animal hunts that people could watch from their seats.
The Circus Maximus was 621 meters long and 118 meters wide. Historians estimate that it could hold an amazing 250,000 people at once (some say it may have been closer to 300,000). Even more could watch from the surrounding hillsides. There is seating for around 150,000.
While you may be more familiar with the Roman Colosseum, by comparison, that stadium only ever held 50,000 spectators.
In any case, it’s hard to imagine a city accommodating that many visitors all at once!
As Christianity took over Rome, the stadium was used less. By the 6th century AD, it was no longer in use. The space it sat on is now a public park and little of the ruins remain because of a combination of theft of the building materials and degradation from flooding and the passage of time. However, concerts have been held on the site, including shows by Genesis and The Rolling Stones. – WTF fun facts
Source: “Circus Maximus – History and facts of the largest circus in Rome” — Rome.net
Can’t wait for some redneck to try and point out the Indy 500 track even though it’s a non-enclosed racetrack.