Bulgaria
Bulgaria occupies a portion of the eastern Balkan peninsula, bordering five countries—Greece and Turkey to the south, Macedonia and Serbia to the west, and Romania to the north. The land borders have a total length of , and the coastline has a length of . Its total area of ranks it as the world's 105th-largest country. Bulgaria's geographic coordinates are 43° N 25° E. The most notable topographical features are the Danubian Plain, the Balkan Mountains, the Thracian Plain, and the Rhodope Mountains. The southern edge of the Danubian Plain slopes upward into the foothills of the Balkans, while the Danube defines the border with Romania. The Thracian Plain is roughly triangular, beginning southeast of Sofia and broadening as it reaches the Black Sea coast.
Geography of Serbia
Serbia is a sovereign state situated at the crossroads of Central and Southeast Europe, covering the far southern edges of the Pannonian Plain (Vojvodina) (a region Central Europe) and the central Balkans. It shares borders with Bosnia-Herzegovina, Bulgaria, Croatia, Hungary, the Republic of Macedonia, Montenegro, Romania and Albania through the disputed territory of Kosovo. It is landlocked, although access to the Adriatic Sea is available through Montenegro, and the Danube River provides shipping access to inland Europe and the Black Sea.