Amphitheatre of Serdica, Sofia

The Amphitheatre of Serdica once stood in the ancient Roman city of Ulpia Serdica, which is modern-day Sofia, the capital of Bulgaria. Discovered in 2004, with follow-up excavations in 2005 and 2006, the amphitheatre in present-day Sofia dates back to the 3rd-4th centuries AD. Built atop a damaged 2nd-3rd century theater ruined by the Goths, it was only in use for a short time and left abandoned by the 5th century.

The Amphitheatre of Serdica was one of the largest in the eastern part of the Roman Empire and the largest in what is now Bulgaria. It was located outside the city walls of Serdica and hosted gladiator battles and fights between wild animals. These events were advertised at the city's entrance.

Since 1919, the presence of a Roman amphitheater in ancient Serdica has been suggested. A stone plate displaying the amphitheater's facade and gladiator battles with animals, including crocodiles, bears, bulls, and wild cats, was discovered near Bulgaria's Council of Ministers building. This plate, likely used as an advertisement for such events, is now exhibited at Sofia's National Archaeological Institute with the Museum of Bulgaria.

The amphitheater was found by accident in 2004 during the construction of the Arena di Serdica Hotel in Sofia. More arena sections were discovered in July 2006 while excavating the foundation of a nearby National Electric Company office building.

Approximately 1/6th of the hotel's property, including the eastern entrance and a section of the amphitheatre, has been preserved and incorporated into the hotel's ground floor. These remains are open to tourists daily (except Mondays) and feature an exhibition of coins and ceramics found on-site. In 2007, excavation work at the National Electric Company's site uncovered the western entrance and part of the amphitheatre, prompting efforts to halt the planned construction on that site.