Balkans vs Balkan Mountains

Balkans and Balkan Mountains both are nouns.

Word	Noun	Adjective	Verb	Adverb
Balkans	Yes	No	No	No
Balkan Mountains	Yes	No	No	No

As nouns, Balkans and Balkan Mountains are synonyms defined as:

Balkans and Balkan Mountains: the major mountain range of Bulgaria and the Balkan Peninsula

Other synonyms of Balkans include Balkan Mountain Range.

Balkans (noun)	Balkan Mountains (noun)
the Balkan countries collectively	the major mountain range of Bulgaria and the Balkan Peninsula
a large peninsula in southeastern Europe containing the Balkan Mountain Range
the major mountain range of Bulgaria and the Balkan Peninsula