Strandzha, also spelled Stranja, Strandja and Strandza, is a mountain and a cultural region in Bulgaria.
Strandzha is known for the specific architecture that can be observed in Malko Tarnovo, Brashlyan and most other villages, the rich folklore and distinctive rituals, such as nestinarstvo (barefoot dancing on live embers), that preserve numerous pagan elements. Strandzha is an area with a large concentration of ruins of Thracian sanctuaries and sacrificial altars, dolmens and other archaeological objects. The mountain is also the home of the Strandzha National Park - the largest protected area in Bulgaria.
To the southeast, the mountain range extends into the Turkish region of Eastern Thrace, where it is known as Istranca. See the articles for Demirköy, İğneada, Vize, Kıyıköy, Saray, and Çatalca for the relevant sites in the Turkish portion.