The Rila area has an austere alpine beauty, with stone ridges, towering peaks, deep precipices and numerous crystal clear lakes (more than 140) and springs. The name of the mountain is thought to originate from a Thracian word signifying "rich in water".

 Three of the largest Bulgarian rivers spring from the mountain - the Maritza, the Iskar, and the Mesta of the largest tributaries of the Struma also originate here. The river valley separates the mountain into four regions. Twelve of the eighteen highest Rila peaks above 2,700 m, are situated in the eastern region. The main Balkan water shed passes through the central region-between the Black Sea and Aegean basin. The most alpine part is located in the North-western region.The Parangalitza reserve and the group of the Seven Rila Lakes are among the most attractive natural sites.