The Forum of Philippopolis (agora) is the commercial, administrative and religious center of ancient Plovdiv.

The Forum Complex is situated on an area of 20 ha (11 ha open area) and is the largest in the territory of Bulgaria.

It was built during the time of Emperor Vespasian in the 1st century AD and was completed in the 2nd century. The main streets of ancient Philippopolis were gathered at the forum, and there were commercial and administrative buildings nearby, such as Odeon, the city library, the treasury, and others.

A large part of it (about 11 ha) is exposed outdoors along with the restored columns and rows of Odeon's seats in Philippopolis, and the rest lies under modern buildings.

The center of the ancient city and the route of its main street - the cardio maximus, coincide with the modern center of Plovdiv and its main pedestrian zone.