The Amphitheater, in the center of El Djem, is known as the African Colosseum - and with some reason, for it is the fourth largest amphitheater in the Roman world, coming after the Colosseum in Rome, the amphitheater at Pozzuoli, near Naples, and the one at Carthage, of which little now survives. Oval in form, the amphitheater is 149m/486ft long by 122m/400ft across (compared with the Colosseum's measurements of 188m/617ft by 156m/512ft). It is also of impressive height (40m/130ft) - a height which would be still further increased by the canvas sails (vela) which protected the audience from the sun.
It provided seating for over 30,000 (according to some estimates 60,000) spectators of the sporting events, bloody gladiatorial contests and slaughters of criminals by wild animals which were staged in the arena. It was thus too big for a town the size of Thysdrus, and was evidently intended as a demonstration of the city's power and prosperity. Although the amphitheater was used for centuries as a quarry of building stone it is better preserved than the Colosseum in Rome. Restoration work was carried out in the 1970s, and has recently been resumed. Only two-thirds of the circuit of walls with their three storys of arcades have survived. The northwest side was blown up in 1695 on the orders of the Turkish Bey, Mohammed, to prevent it from being used as a stronghold by Berber rebels, who had frequently entrenched themselves within its walls. Each of the three storys originally had 30 arches, of which there remain a total of 68.
Little is left of the tiers of seating in the interior, but under the arena (which measures 65m/213ft by 37m/121ft) can be seen the two intersecting underground passages (excavated in 1908) through which the wild animals and their victims entered the arena. On either side of the passages were cages for the animals and cells for the prisoners. At the entrance is a flight of steps leading to the upper tiers of arcades, from which there are good general views of the amphitheater and of the town.