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.
Nuclear-weapon-free zone
The other European countries west of the former Soviet Union
are small Western European states and surrounded by and aligned with the EU and NATO but not members (Switzerland and European microstates Liechtenstein, Monaco, San Marino, Vatican, Andorra), or Balkan states that have not yet joined the EU (Albania, Bosnia, Montenegro, Macedonia, Serbia and Kosovo).