The amphitheater is distinguished by its remarkable size (126 x 94 meters with an arena of 75.2x43.2 meters), which testify to the importance of the city.
The arena, used for gladiator fights and for naumachie (naval battles), is elliptical and cavea leaning against a natural slope, placed 9 meters below the country floor and is bordered by a channel of water collection and a podium in which there are four entrances; also has a system of caves that served as a shelter for fairs. The system could hold up to 18,000 spectators and was equipped with a wall to which a system of mobile coverage of the grandstands was inserted. Of the 4 original entrances, 2 remain at the end of the major axis of the plant (east-west direction): these stone portals consist of Ionic columns, lintel and triangular tympanum, on which is carved a round shield crossed by a javelin. In the portal addressed to the city it reads that Marco Vecilio Campo built it at his own expense in a fund owned by him and in honor of Augustus and the colony of Lucera.
Adjacent to the building are the remains of gyms, infirmaries and other buildings for the shelter of gladiators. The amphitheater was probably damaged following the conquest of the city by the Byzantine emperor Constans II in 663. Following its abandonment, it was used as a stone quarry and gradually buried.
In 1932 some excavations brought to light the first significant remains of the Roman amphitheater, whose excavation and restoration work ended in 1945.