The Rome IndexCircus Maximus
Ancient Rome's chariot-racing track — the world's largest stadium, now a public park.
What it was
At its height the Circus Maximus held around 250,000 spectators for chariot races — larger than any modern sports venue. The track remained in use for nearly a thousand years.
What's there now
A long, oval public green space in the valley between the Aventine and Palatine hills, free to enter and one of the more underrated open spaces in the city center.
Visiting
A good add-on to the Baths of Caracalla nearby, or a stop on the way to Testaccio — the shape of the original track is still clearly readable from the surrounding slopes.