The Upper Thracian Plain (, Gornotrakiyska nizina) constitutes the northern part of the historical region of Thrace. It is located in southern Bulgaria, between Sredna Gora mountains to the north and west, a secondary mountain chain parallel to the main Balkan Mountains; the Rhodopes, Sakar and Strandzha to the south; and the Black Sea to the east.
The Upper Thracian Plain (Gornotrakiyska nizina) is located in southern Bulgaria, encompassing the northern part of the historical region of Thrace. It borders the Sredna Gora mountains to the north and west, a secondary mountain range parallel to the main Balkan Mountains; the Rhodopes, Sakar, and Strandzha ranges to the south; and the Black Sea to the east.