The Kamchia Reserve covers the lower reaches of the Kamchia River, the municipalities of Avren and Dolni Chiflik. The reserve is located about 25 km south of Varna, near the resorts of Kamchia and Shkorpilovtsi. Because of its important nature conservation and ecological significance, in 1977 it was included in the World Network of Biosphere Reserves as part of the UNESCO Man and Biosphere Programme for the protection of the most representative ecosystems on the planet. Particularly valuable for the reserve are the longos forests along the lower reaches of the Kamchia River. In the protected area of Longosa (230 hectares, 70 of which are forest area and preserved longos forests) there are diverse plant and animal species.