The Balkans (often referred to as the Balkan Peninsula, although the two are not coterminous; Albanian: Gadishulli Ballkanik and Siujdhesa e Ballkanit; Bosnian, Croatian and Serbian: Balkansko poluostrvo and Balkanski poluotok; Bulgarian and Macedonian: Балкански полуостров, transliterated: Balkanski poluostrov; Greek: Βαλκανική χερσόνησος, transliterated: Valkaniki chersonisos; Italian: Penisola balcanica; Romanian: Peninsula Balcanică; Slovene: Balkanski polotok; Turkish: Balkan Yarımadası) is a geopolitical and cultural region of southeastern Europe.

The region takes its name from the Balkan Mountains in Bulgaria and Serbia, while the name "Balkan" in Turkish means "a chain of wooded mountains", for which there is one of the theories for the name's origin. The region was established in Antiquity when the peninsula became widely accepted with the Thracian name "Peninsula of Haemus"(the name for the region until the Late Middle Ages), which name also derives from the Balkan Mountains, with the name "Haemus Mountains" in the period. The Balkans are highly mountainous; Mount Musala (2,925 metres (9,596 ft)) in the Rila mountain in Bulgaria is the highest. Many linguistic families meet in the region, including the Slavic, Romance, Hellenic, Albanian, and Turkic language families, while the main religions are Orthodox Christianity, Roman Catholicism and Sunni Islam.