The arena is the only remaining Roman amphitheater to have four side towers and with all three Roman architectural orders entirely preserved. It was constructed in 27 BC – 68 AD and is among the world’s six largest surviving Roman arenas. A rare example among the 200 surviving Roman amphitheaters, it is also the best preserved ancient monument in Croatia.
The amphitheater was erected in Tuscan style, covering an area of 11, 466 m2. It is estimated that it could receive approximately 23,000 spectators. The exterior wall is constructed in limestone. The part facing the sea consists of three stories, while the other part has only two stories since the amphitheater was built on a slope. The maximum height of the exterior wall is 29.40 meters. The first two floors have each 72 arches, while the top floor consists of 64 rectangular openings.