The Large Theatre was built by exploiting the natural slope of the hill for the construction of the auditorium. The staircase was separated into three areas with corridors, which were in turn divided into five sectors, and was based on a passage with a barrel vault.
It was built around the middle of the 2nd century BC and significantly restored according to the Roman stlye. An inscription, visible at the entrance of the corridor that provides access to the east and that is one of the very few representations known with reference to the name of the architectus, recalls the works carried out in the Augustan age by Marcus Artorius Primus.
These works concern the scene and the stage, the adoption of the velarium, a large tarp used as a cover for the warmer days and the numbering of the seats. In the theatre they represented comedies and tragedies of Greek-Roman tradition. The theatre was the first large public building completely freed from the deposits of the eruption.
Date of excavation: 1764-1765; 1767-1769; 1773; 1789; 1791-1794; 1902; 1951.