The ancient theatre at Corinth was built in the 5th century BC, modified by the Romans, and later used for gladiatorial combat and animal hunts by flooding the orchestra — a repurposing the Romans applied to theatres across the empire. The theatre is slightly separate from the main archaeological zone, on the northwestern slope of the city plateau.
The seating is cut into the hillside in the Greek fashion and retains much of its stone. It is less visited than the main agora complex, which means you often have it more or less to yourself. The setting — looking out over the modern town toward the Gulf — is worth the short detour.