The Colosseum, (the Flavian Amphitheatre) is one of Rome's most famous buildings and enduring monuments to the culture of the ancient Romans. Construction was initiated by the Emperor Vespasian around 72 AD. His son Titus reigned over its completion and the official opening ceremonies, about 8 years later, in 80 AD. It was built near the site of Nero's Domus Aurea "Golden House". This is significant in that his successor, Vespasian wanted to erase the memory of Nero's extravagant reign from the minds of Romans. It got its popular name, the Colosseum, because of Nero's colossus (120 ft. high) statue of himself, which was nearby.
The huge theater was originally built encompassing four floors. The first three had arched entrances, while the fourth floor utilized rectangular doorways. The floors each measured between 10,5-13,9 meters (32-42 feet) in height. The total height of the construction was approximately 48 meters (144 feet). The arena measured 79 x 45 meters (237-135 feet), and consisted of wood and sand. (The word "arena" is derived from the Latin arena, which means "sand.") Nets along the sides protected the audience.
The Colosseum had a total spectator capacity of 45,000-55,000. The Amphitheater is built of travertine outside, and of tufa and brick in the interior. The main pedestals were built of marble blocks weighing 5 metric tons (11,000 pounds.) Initially the huge marble blocks were held together by metal-pins. However, the pins were soon carried off by thieves, and had to be replaced by mortar. The total amount of marble needed for the construction measured approximately 100,000 cubic meters. It was carried by 200 ox-pulled carts, which supplied a sufficient flow of needed materials.
There were no less than 76 numbered entrances and 4 additional entrances reserved for the Emperor, other VIP's and the gladiators. The Colosseum was designed for easy crowd dispersal; the entire audience could exit the building in five minutes. The interior was divided into three parts: the arena, the podium, and the cavea. Now more than two-thirds of the original building has been removed and the rows of the seats in the cavea are missing. It is very similar to other amphitheaters except this one is much bigger.
The audience, upon entering, climbed sloping ramps to their seats, according to gender and social class. Obviously, the higher one's social status, the better their seating arrangement would be. For example, women (excepting spouses and perhaps imperial family) and the poor, stood or sat on wooden benches in the fourth tier. For inclement or very hot weather conditions, an enormous, colored awning (velarium) could be stretched overhead to protect the crowd.
A wooden floor covered subterranean chambers where the gladiators and animals were kept waiting to perform. There is some debate over the idea that the Colosseum was occasionally flooded for mock naval battles. There were canals in place that could have been used for this purpose but the brick used in construction was not the same type of material that they normally used in water resistant materials.
The Colosseum was the Empire's primary stage for gladiatorial combat for nearly 4 centuries. In a show of Rome's wealth and extravagance, during the opening ceremonies in 80 AD, 100 days of the games were held.