Aquae Calidae, Bulgaria Aquae Calidae, Bulgaria Aquae Calidae (Latin for warm waters), also known as Therma and Thermopolis in the Middle Ages, was an ancient town in Thrace located in the territory of today's Bulgarian port city of Burgas. It was built around thermal baths using the hot springs and became one of the most important spa centres of ancient times. The site and baths of Aquae Calidae have been visited in the course of history by several important rulers from Philip II of Macedon to the Eastern Roman emperors Justinian I and Constantine IV, the Bulgarian ruler Terwel and the Ottoman Sultan
Celsa (Roman city) the "scaenae frons" (stage) walls and tiers of seats ("cavea") have been found. Many small objects as lamps, Pompeian red slip dishes, Iberian ceramics, etc., as well as small bronzes, sculptural remains, coins and small pieces of jewellery are also preserved. A nearby museum displays many of the finds. Celsa (Roman city) Celsa was an important pre-Roman and Roman city located near the modern town of Velilla de Ebro. Recent excavations have brought to light many rich private and public buildings which give a glimpse of its former grandeur. Celsa was originally an Iberian settlement, called "Kelse", of the Ilergetes