The remains of the important Roman city of Traianoupolis are located 14 km east of Alexandroupolis. The city was founded by the Emperor Marcus Victor Trajan (98-117 AD) on the main axis of the prominent Via Egnatia. The location was probably chosen because of the thermal springs, which operate until today.

The Romans maintained the Greek  institutions  on civil organization and according to inscriptions and coins testaments we are aware of the existence of a sacred senate, several municipalities and tribes.

The most remarkable building is Hannah, a rectangular arched building dated back to the second half of the 4th century BC, which was used as a guesthouse. Behind this building the medicinal baths of the Ottoman era (16th century) are located. Ruins of a church can still be seen on the hill of Ayios Georgios, a possible Acropolis of the Roman settlement. Visitors can also see the remnants of a Turkish opium den, known as Isiklar, as was described by the Turkish traveler Evliyia Tselembe in 1668.

Trajanoupolis, with the homonyms thermal springs, not only hosts guests for spa and mineral water treatments, but also many others who want to enjoy the beauty of the area or just visit the spa. The reason that these thermal springs are so famous is that are rich in hydro-sulfur-chloride-sodium and their thermal mineral water can help to the treatment of many diseases such as rheumatism, slipped disk, and problems in the liver and kidneys.

Those who visit the spa can choose whether to stay in the hotel within the premises or in hotels located nearby.