Sliven municipality is situated in the south-eastern region of Bulgaria and covers 1367 sq.km. It borders on Yambol municipality to the south, Bourgas district to the east, Kotel municipality to the north, Tvarditsa municipality to the west and on Nova Zagora municipality to the southwest. Sliven lies at the feet of the southern flanks of Slivenska Planina mountain (1181m) which borders the east Balkan. South and southeast it is opened to the Sliven field which monotony is broken by the isolated bulk-like heights (up to 300m sea elevation). North of town of Sliven and close to the living quarters of the town the light imparts a blueish tinge to the prophyry massif known as the Sinite Kamani or Blue Rocks. The park of the same name includes 6684.3 ha of the Balkan. Sliven municipality is located in the region of the sub-Balkan fields and in the transitional continental climatic zone. Average annual air temperature is 12.4°С. Winter average monthly temperature is 1.2°С (the winters are mild) and the summers are relatively dry - 23.2°С. Autumns are longer than springs.