The materials used were different according to the burdens which had to bear: in the pillars and exterior walls was used stone and brick and stone lighter nearer sand. The concrete was used in the construction of vaulted floors of the corridors. 100,000 M of travertine and 300 tons of metal to the staples that kept United blocks were used in its construction. Unlike the first amphitheaters, whose location is sought was in hills to offer support to the walls, the Colosseum is a slope of stone and cement, 48 meters high, and 188 long and 156 m wide with a capacity for 50,000 spectators who could enter or leave less than three minutes thanks to a complex network of passageways and exits. The consecutive numbering on the entrance arches corresponded with the numbering of the seats. From the outside presents four floors of arcades in which you can see the superimposition of orders, in columns of three quarters with purely decorative function: down the toscano, in the Middle the Ionian and above the Corinthian. The outer wall is supported by 80 solid pillars, which in turn are connected with interiors by means of concrete vaults.
There is nothing of the pavement of the arena: the current visitor can see the maze of Chambers and passages that had below; talk hidden gar yl Sky made to men and beasts appeared from under the ground. Level of the soil, to the right, the main door of the building is situated or porta triunphalis and the front is the door where the victims were evacuating or porta libitinaria, the cavea or bleachers began to four meters above the level of the track, with one platform (podium) protected by a brass railing; more category public marble seats were lined on the podium. Above is escalonaba the stand destined to the ordinary public, divided into three zones.