The Roman Thermal baths are the most preserved remains of the Antiquity in Bulgaria, as well as the largest public building on the territory of the country.
Built during the Roman epoch, towards the end of the 2nd century, they represent the largest Roman bath on the Balkans. According to the studies, the height of the vaulted structures was over 20 m, and the total area of the facility is about 7000 m². The bathrooms were in operation until the end of the third century. They had an important social function in the ancient Odessos, which from 15 BC. is part of the Roman Empire in the province of Moesia, but retains some autonomy (such as the right to cut their coins and to have no Roman garrison). As the main port of Moesia, the city was heavily influenced by the Roman culture, which is also testified by the thermae.
Today, during summer, summer theaters function and concerts are held.