Mountain range, Balkan Peninsula , southeastern Europe.
Extending southeast from Bulgaria through Macedonia and Greece, the range is drained by tributaries of the Maritsa River . It forms an important climatic barrier, protecting the Aegean lowlands from cold northerly winds. The mountains were a refuge for Slavic peoples during the period of Turkish rule (15th19th century), and ancient customs survive. The lakes, river valleys, and extensive forests form the basis of a tourist industry.