Serdica was an important Roman city in the province of Thrace, and in the 4th century it was a favourite residence of Emperor Constantine the Great, who is said to have called it "my Rome". Here you can see the paved decumanus maximus, the city's main street, along with the remains of houses, baths, workshops and an early Christian basilica, laid bare beside the traffic of the modern city.
Nearby, the red-brick Rotunda of St George, built in the 4th century and still standing in a courtyard behind the Presidency, is the oldest building in Sofia.
The ruins are free to visit and easy to combine with a walk along Vitosha Boulevard.
