The ancient ruins of Maronia are located about 45 km from Alexandroupoli in Thrace. The settlement was founded by settlers from Chios on the southwest of Ismaros (another ancient city) in the middle of the 7th century BC and developed into a mighty city-state. The fortification of the city was 10 km long and included about 4,000 acres from the shore to the top of Ismaros.
The ruins include: some of the walls and towers, an ancient theater, a Roman market and various parts of the city. Maronia is renowned since antiquity for producing wine. It was here that King Maron gave Odysseus red wine which he gave to the Cyclops to aid in his escape. Today there are still vineyards in the area.