
Римскиот театар во Трст се наоѓа во подножјето на ридот Сан Гиусто, со поглед кон Јадранско Море. Изграден е во I-II век, за време на императорот Трајан.
The Roman theater was soon built entirely of stone, with the exception of the upper part of the steps and the upper part of the stage, which were of wood. The statues discovered around the complex are kept in the City Museum of Trieste. Several inscriptions from the Trajan period were also discovered. Three of them mention Petronius Modestus, someone closely connected with the construction and development of the theater in the 1st century. Today, the Roman theater has been renovated and is available for open performances, although its capacity is now less than its former 6,000 spectators.