The land area of Bulgaria is 110,550 square kilometers. The country is situated on the west coast of the Black Sea, with Romania to the north, Greece and Turkey to the south, Serbia and Macedonia to the west. Considering its small size, Bulgaria has a great variety of topographical features. Even within small parts of the country, the land may be divided into plains, plateaus, hills, mountains, basins, gorges, and deep river valleys.
In 1991 Bulgaria had a total border of about 2,264 kilometers. Rivers accounted for about 680 kilometers and the Black Sea coast for 400 kilometers; the southern and western borders were mainly defined by ridges in high terrain. The western and northern boundaries were shared with Yugoslavia and Romania, respectively, and the Black Sea coastline constituted the entire eastern border. The Romanian border followed the Danube River for 464 kilometers from the northwestern corner of the country to the city of Silistra and then cut to the east-southeast for 136 kilometers across the northeastern province of Varna. The Danube, with steep bluffs on the Bulgarian side and a wide area of swamps and marshes on the Romanian side, was one of the most effective river boundaries in Europe. The line through Dobruja was arbitrary and was redrawn several times according to international treaties. In that process, most inhabitants with strong national preferences resettled in the country of their choice. Borders to the south were with Greece and Turkey. The border with Greece was 491 kilometers long, and the Turkish border was 240 kilometers long.
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