Thrace /ˈθreɪs/ is a historical and geographic area in southeast Europe. As a geographical concept, Thrace designates a region bounded by the Balkan Mountains on the north, Rhodope Mountains and the Aegean Sea on the south, and by the Black Sea and the Sea of Marmara on the east. The areas it comprises are southeastern Bulgaria, northeastern Greece, and the European part of Turkey. The biggest part of Thrace is part of present-day Bulgaria. In Turkey, it is also called Rumelia.