Strandzha Nature Park is the largest protected area in Bulgaria spanning a territory of 1,161 square kilometres (448 sq mi) in the Strandzha Mountain in the extreme south-eastern corner of the country on the border with Turkey. It was established on 25 January 1995 to protect ecosystems and biodiversity of European importance, as well as the traditional cultural, historical and folklore heritage of the region. The altitude varies from 710 metres (780 yd) on Gradishte Peak to 0 metres (0 yd) at the Black Sea coast with average length of 50 kilometres (31 mi) from west to east and 20 kilometres (12 mi) from north to south.

Strandzha is a mountain massif in southeastern Bulgaria and East Thrace the European part of Turkey. It is in the southeastern part of the Balkans between the plains of Thrace to the west, the lowlands near Burgas to the north, and the Black Sea to the east. Its highest peak is Mahya Dağı in Turkey, while the highest point on Bulgarian territory is Golyamo Gradishte. The total area is approximately 10,000 km2 (3,861 sq mi).