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.
Eurosphere
According to Mark Leonard, the Eurosphere includes 109 countries. In Europe, this includes the 28 member states of the EU, applicant countries wishing to join the EU, the Western Balkans, and European Commonwealth of Independent States countries (including Armenia, Belarus, Georgia, Moldova, Ukraine, and transcontinental Kazakhstan). Curiously he does not mention Western European countries such as Norway who are already integrated into the EU's single market. Outside Europe, he lists every African country and every Middle Eastern country, as well as the countries forming the eastern border of the Eurosphere such as Iran, Azerbaijan, Russia, and Central Asia.