The amphitheatre is the most important monument of the former Roman colony that we should admire, some two thousand years after its construction. Its architecture is entirely designed in relation to its vocation of place to great shows, hosting a large audience. In their initial rise, the bleachers could receive approximately 21 000 viewers, streams were cleverly organized by a network of doors, galleries and stairs, on several floors.Become at the beginning of the middle ages a city close and fortified, the building was cleared only in XIX century. He himself then for part, its original function, including bullfighting, which earned him his current common appellation of "arenas".It is today the monument of the most visited city, bringing the image of Arles in the world.With a major axis of 136 meters in length and a minor axis of 107 meters, the amphitheatre of Arles is slightly larger than that of Nîmes and the 20th ranked among those of the Roman world. It has a shape of an ellipse. The façade includes two levels of sixty semicircular arches, separated by the abutments, massive rectangular section. A wider opening points out the ends of the two axes of the monument. The main entrance was not North as today, but the West where we can see the remains of a staircase overlooking the city.The cavea, space reserved for spectators, included 34 stands, divided into four series: the maeniana, where viewers were divided according to their social status. It is estimated the initial capacity of the monument to some 21,000 people. To allow visitors to access the different stands, had developed an ingenious device of circular galleries, horizontal passages, and prepared Alternatively stairs.On the ground floor, the outdoor Gallery is particularly noteworthy, especially for its coverage of large monolithic slabs. She gave access to an indoor gallery, vaulted arch, which opened on the first maenianum and on the lower part of the second. The outdoor Gallery, stairs also allowed to reach the first mezzanine, whence it had access to the second maenanium either the outdoor Gallery of the first floor. This vertical and horizontal circulation system allowed to reach the highest level of the building. A penthouse, now defunct, surmounted the façade: there were fixed the masts used to stretch an awning to protect spectators from the Sun.The central part reserved for the games and fighting (the arena itself) was separated from the stands by a carefully matched wall: the wall of the podium dressed in large slabs of stone. The soil of the track was higher about 2 meters than the current level. Indeed, it consisted of a wooden floor, which the blades were based on a stone bead, at the top of the lower part of the podium. The machinery needed for the shows was staying between the walls and floors that ensured the stability of the arena.