The Colosseum, the grandest amphitheater ever made, stands as a symbol of the epic Roman Empire. The Flavian Amphitheater, commonly called the Colosseum, got its nickname because of its colossal dimensions and because of a colossal statue of Nero that was nearby. Construction of the amphitheater began in 70 A.D. and was completed in 80 A.D. It is known for its multi-level system of vaults made of concrete. The elliptical amphitheater is 156 meters long, while its circumference is 527 meters. Built with travertino, tufa and bricks, its four story exterior wall was 50 meters high. Three of the four stories contain arches divided by columns in differing styles in this order,the first story has Doric style, the second story uses the Ionic styles and the third has the Corinthian. The fourth story has no arches but is decorated with Corinthian lesene. The Colosseum was also constructed with a covering system that sheltered spectators from rain or hot sun. Four entrances led into the arena with eighty arcades through which the people reached the upper stories. The public was seated on three possible ranges of seats, the lowest was reserved for knights, the middle was for citizens, the third and highest was for the common people. There was also a place where people could stand. The amphitheater could hold 50,000 people. Fights between gladiators, men and wild animals and navel fights took place in the Colosseum. Historians are not sure whether or not Christians were martyred during the imperial persecutions, but Pope Benedict XV declared the amphitheater consecrated to Christian martyrs. This papal measure saved the Colosseum from destruction as it was considered a real stone-quarry. According to an 18th century prophecy, the end of the Colosseum is bound to the end of Rome and the end of Rome to that of the world. Earthquakes, spoliations of travertino and iron damaged it greatly until 1750 when sound restoration works began. The Colosseum, had two major impacts on Roman culture, its tremendous architectural structure and its effect on the social lives of Romans. The Colosseum is a monument to architectural styles that were popular in the era of the Roman Empire. In the construction of the Colosseum, the brightest minds in architecture were brought together to construct this amphitheater which was unlike anything built before. The methods, styles and materials used in construction were state-of-the-art for the time and still stand today as a monument to the great Roman Empire. The Colosseum brought thousands of people together for political reasons, such as for the speaking of a leader or another important figure,and for entertainment, such as a circus or chariot racing. Fights, between Gladiators, were also held in the colosseum. It is believed that during the imperial persecutions, Christians were sent into the pit to be eaten by lions. They would even bring exotic animals, some of which most people had never seen, into the Colosseum to be hunted by warriors. These events helped unify the people while others polarized them. People came from all ends of the empire to watch events in the Amphitheater. This meant people coming in would get information and ideas and would take them back home. This would create cultural diffusion throughout the empire. The Colosseum was the prototype for the development of modern stadiums and gathering places, such as football stadiums and convention centers. The Colosseum became a model for future students of architecture and engineering. Before the Flavian Amphitheater, construction of amphitheaters depended on location. Because the Greeks did not know how to build artificial slopes in the seats, they had to make the seats on the side of a hill with the stage or center area below. With the construction of the Colosseum it was possible to make them anywhere they wanted to. Now stadiums can be constructed anywhere, no longer dependent on the natural landscape, thereby letting people gather for social and political and entertainment reasons.