Central Bulgaria is traversed from east to west by ranges of the Balkan Mts. ( Stara Planina, or "Old Mountains" in Bulgarian). A fertile plateau runs north of the Balkans to the Danube River, which forms most of the northern border. In the southwest is the Rhodope range, which includes Bulgaria's highest point, Musala Mt. (9,592 ft/2,923 m). The Thracian plain lies south of the Balkans and east of the Rhodope. The Danube, the Iskŭr, the Maritsa, and the Struma are the principal rivers.
About 85% of the people are Bulgars. Turks make up almost 10% of the population, and about 5% are Romani (Gypsies). There are also smaller groups of Macedonians and Armenians; however, Bulgaria, with its historic claim to Macedonia, refuses to recognize Macedonians as distinct from Bulgars. Bulgarian is the predominant language. Most of the population belongs to the Bulgarian Orthodox Church; in 1953 the Bulgarian patriarchate, which had been disbanded in 1946, was reestablished. There is also a substantial Muslim minority.