The Amphitheatre is located 200 metres to the northeast, outside the city walls of Pula, in accordance with the Roman land division network. It is believed that construction began during the reign of Emperor Augustus and was financed by the imperial treasury. The two central axes of the outer wall measure 132.5 m and 105.1 m, and the maximum height is 32.45 m. The Amphitheatre was built in the Tuscan style, had its own drainage channels, and is estimated to have accommodated approximately 23,000 spectators. The Amphitheatre has four levels, although the eastern part, on higher terrain, has only the two upper levels. At the primary axis of the ground level, the arches are larger than the others, emphasizing the main entrances.
The first level of the auditorium was built around the entire circumference of the amphitheatre with 72 semi-circular arcades. The second level had a encircling gallery with 64 square windows, covered by a sloped roof of ceramic tiles. The axes of the oval arena measure 67.9 by 41.6 m. Below the arena is the auxiliary subterranean chamber, carved into the bedrock and partially constructed. It served for storing various technical aids. In case of bad weather, the auditorium was covered with a canvas using pulleys and ropes. Wooden masts, supporting the canvas, passed through designated openings in the stone gutter.
The Amphitheatre in Pula differs from others in having four rectangular towers housing wooden staircases. Two cisterns at the top of each tower collected rainwater.
Gladiatorial fights and animal hunts were organised in the amphitheatre. Entry was free, but seating arrangements strictly followed social hierarchy. Public trials were held in the arena, and the ad bestias punishment of murderers, robbers, and rebels was performed here. The historical story of the martyrdom of St Germanus, the patron saint of Pula, is associated with Pula's amphitheatre.
After the prohibition of gladiatorial shows in the early 5th century, the amphitheatre was abandoned to a process that stripped much of its masonry, but it always remained public property. For centuries, it attracted the attention of travellers, artists, and architects. Archaeological investigation of the amphitheatre began in the mid-18th century, and its conservation continues to this day.