The Republic of Bulgaria is situated in the eastern part of the Balkan Peninsula. The border with the Black Sea to the east is 378 km long, starting from the village of Vama Veke to the north up to the mouth of Rezoska River to the south. It borders Romania to the north and the frontier is 609 km long, stretching from the mouth of the Timok River, along the Danube River up to the town of Silistra and continuing from Silistra, crossing Dobrudza, up to the village of Vama Veke by the Black Sea.
The border with Serbia and Macedonia to the west is 506 km long. It lies across the hills of Balkan Mountain called Ograzhden, Maleshevska, Vlahina, Osogovo, Milevska, Rui, and the west part of Balkan Mountain, goes along the Timok River and reaches the Danube.
Bulgaria adjoins Greece (the length of the border is 493 km) and Turkey (border length – 259 km) to the south. The boundary with Greece starts from Peak Tumba in Belasitsa Mountain, crosses the mountains of Slavyanka and the Rhodopes and gets up to Maritsa River.
The border with Turkey starts from Maritsa River, follows the mountain ridges of Derventski Heights and Strandzha Mountain and reaches the mouth of the Resoska River.
Bulgaria is a country of mountains and highlands. More than 37 mountains are situated on its territory and most of them are located in the southwestern part. The Balkan Mountain (Stara Planina) is the longest and the biggest mountain, which divides Bulgaria into a northern and southern part. Second in length is Sredna Gora. The most impressive are Rila and the Rhodopes Massif, which includes the mountains of Rila, Pirin, Rhodopes Slavyanka, and Stargach. East of that massif two lower mountains are situated – Sakar and Strandzha. Very popular is the mountain of Vitosha with its Cherni Vrah (Black Peak – 2290 m high), in the skirts of which the Bulagarian capital – Sofia is situated. There are many low mountains located between the border with Serbia and Rila Mountain. Those are Rui, Ezdimir, Stadza, Lyubash, Cherna Gora, Verila, and Golo Bardo, where the Reserve Ostritsa is placed, a reserve luxuriant of endemic flora species. The mountain group of Osogovo and Belasitsa is situated in the southwestern part of Bulgaria. It includes the mountains of Osogovo and Belasitsa (above 2000m high), as well as Maleshevska Planina, Vlahina, and Ograzhden. Belasitsa, however, is situated on the territory of Bulgaria, Greece and Macedonia.
The mountains of Bulgaria are suitable for tourism and sport. Very good skiing conditions offer four big ski centres: Borovets, Pamporovo, Aleko and Bansko. Smaller ski centres with local significance are Semkovo, Panichishte, Rilski Ezera (Lakes of Rila), Malyovitsa, Petrohan, Kom, Strazhata, Beklemeto, Uzana, Chumerna, Zdravets, Byala Cherkva, Persenk, Yundola, Cigov Chark. A centre of the mountaineering is Malyovitsa Peak (2730m), as well as Vihren, Rayski Skali (Heaven Rocks), The North Dzhendem, Lakatnik, Karandila and the gorge of the Erma River. The conditions are also favourable for mountain marathon, cycling, delta- and paragliding, canoe an kayak.