The Roman Colosseum is one of the best known ancient structures, partly because so much of it still remains, but also because
- it is visually arresting with its layers of imposing, arches,
- impressive much-described events went on inside, and
- its purpose is familiar, since we still use colosseums for entertainment today.
Colosseum is also spelled Coliseum, but this wasn't the name by which the ancient audiences, who attended its extravagant, dangerous performances, knew it. The famous Roman Colosseum was known to the ancient Romans as Amphitheatrum Flavium 'the Flavian Amphitheater,' a name honoring the emperors who built it (from A.D. 70-82) and the shape of the entertainment venue.
The medieval historian Bede applied the name Colosseum (Colyseus) to the Flavian Amphitheater possibly because the amphitheater -- which had reclaimed land Nero had devoted to his extravagant golden palace (domus aurea) -- stood beside a colossal statue of Nero. This etymology is disputed.
The Roman colosseum may have held 87,000 spectators and several hundred fighting animals. The colosseum was about 160 feet high and covered about six acres. It was the tallest ancient Roman structure. It was located between the Caelian and Esquiline hills.
Reference: Great Buildings - Colosseum
