English: Rila National Park, the largest national park in Bulgaria, is located about 100 km. south of Sofia, in the central and highest regions of the Rila Mountains. The Park contains rare and endangered wildlife species and communities, self-regulating ecosystems of biological diversity, as well as historic sites of global cultural and scientific significance. Some of the largest rivers in the Balkan Peninsula originate here. The name Rila is derived from the Thracian word roula, meaning ‘lots of water.’ According to that there are located many beautiful lakes, like Seventh Rila lakes, Musala lakes and etc. The highest lake is located under the Musala Peak, its the coldest and the deepst one.