The Old River, Stara Reka in Bulgarian, is a nature reserve within the Central Balkan National Park, created to preserve the unique complex of broadleaf, coniferous, and mixed forests of the Balkan Mountain Range (Stara Planina). It covers the watershed of the Stara Reka River above the city of Karlovo. Winding between steep cliffs and dotted with inviting pools, this is one of the most beautiful rivers in Bulgaria; its silky waters tumbling over moss-covered boulders and past slopes thick with beech, the scene shifts with every season.
The reserve is best known for its plant diversity and the remarkable combination of forest types it supports. In autumn, Stara Reka resembles an illustration from a fairy tale: the canopy ignites in vivid yellows and golds above a forest floor thick with fallen copper leaves, a spectacle that captivates visitors long after they have left. In terms of endangered plant species, it ranks among the most significant reserves in the country, home to the thermophilic hornbeam, the European hornbeam, and the water hornbeam, as well as beech, fir, and common spruce.
The numbers are remarkable: more than 45 plant species listed in the Bulgarian Red Book inhabit this reserve, twenty of which are not found elsewhere in the world, and three of which exist nowhere outside its boundaries. Sixty-five species of vertebrates are permanent residents, among them the golden eagle, the white-tailed buzzard, the great and little goshawk, and the owl; all threatened with extinction. Amphibians and reptiles include the tree frog, the blind frog, and the common rain frog. There are also frequent reports of the lynx, a species considered to have vanished from Bulgaria entirely in the late 1940s.
