Spread over an area of over 27,000 ha, at an alti­tude between 1008 and 2914 m in the Pirin Moun­tains, south­west Bul­gar­ia, the site com­pris­es diverse lime­stone moun­tain land­scapes with glacial lakes, water­falls, caves and pre­dom­i­nant­ly conif­er­ous forests. It was added to the World Her­itage List in 1983. The exten­sion now cov­ers an area of around 40,000 ha in the Pirin Moun­tains, and over­laps with the Pirin Nation­al Park, except for two areas devel­oped for tourism (ski­ing). The dom­i­nant part of the exten­sion is high moun­tain ter­ri­to­ry over 2000m in alti­tude, and cov­ered most­ly by alpine mead­ows, rocky screes and sum­mits.