UNESCO says:
Extending over an area of 27,400 ha and lying at an altitude of 1,008–2,914 m in the Pirin mountains, in south-west Bulgaria, Pirin National Park has a limestone Balkan landscape, with lakes, waterfalls, caves and pine forests. The rugged mountains, with some 70 glacial lakes scattered throughout them, are home to hundreds of endemic and rare species, many of which are representative of the Balkan Pleistocene flora. The mountains also have diverse and unique landscapes of great aesthetic value.
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