Sliven is a province in central Bulgaria. Its main city is Sliven, while other municipalities are Kotel, Nova Zagora, and Tvarditsa. The administrative town is situated at the foot of the unique rock massif "Sinite Kamani" (The Blue Rocks), very close to mineral springs. The town is famous for its clean fresh air, clean water sources, mild winter and cool summer. Sliven is the only Bulgarian town that has never changed its Slavonic name, though it is one of the oldest settlements in Europe. Here lived Thracians, Romans, Slavs, and Ancient Greeks. The first Roman settlement on this place - Tuida ( The 3rd century BC) was a famous trade centre. Sliven was mentioned as a big town for the first time in 1153 by the Arab traveller Idrisi. The 'Sinite Kamani' Nature Park located in the area is famous for its nature landmarks. Halkata – the arc-shaped rock garland, possessing, according to the legends, magic force - is one of the symbols of the town of Sliven. The forms that the nature has sculptured in the cave Zmeevi dupki – Zmejat, Orelat and Vladishkija tron are amazing. The ancient beech forest in the vicinity of the Kushbunar spring in the region of Karandila is quite picturesque. The specific climate and lay conditions of the nature park determine the great diversity of flora and fauna. The plant species are more than 1000, about 900 of which are representative of high species. The invertebrate animals are represented by 235 species – eight species of fish, nine species of amphibians, nineteen species of reptiles, 165 species of birds and 34 species of mammals. The lay is of typical mountain type – steep and ravine slopes and at sea level between 290 and 1181 meters above the sea level. The north and northwest winds, the wind called bora, famous also as the wind of the town of Sliven and the night breeze are typical for the region. Through the park flow many rivers and their beds form numerous shoots, pools and waterfalls. The economy of Sliven has centered around industry since the early 19th century. In 1834, Dobri Zhelyazkov established the first factory in Bulgarian lands, thus starting industrial development in Bulgaria. Sliven was one of the largest industrial centers in Bulgaria, playing an important role during the Bulgarian National Revival. It has long-lived traditions in textiles, machine-building, glass-making, chemical production, and the technical аnd food industries. Following the beginning of communist rule in Bulgaria in 1944, most industries were nationalized and much industrial building and development was spurred. Industry continued to develop until the fall of communism, at which point much of the previously built industry stagnated; many plants and factories were shut down and there was little development. In contemporary times, Sliven has experienced a surge in economy with increased investment, banking establishments and new industries have began to emerge. The dairy industry, which has long been present, continues to grow and thrive. The wine industry, with companies such as Vinprom and Vini Sliven and about a dozen others, continues to grow as grapes are easily grown due to the climate conditions. In terms of heavy industry, Sliven is home to a 3MM plant which produces machinery used to cut metals. The city also produces electric lights and electrical machines. Light industry in sliven is mostly devoted to textiles with many companies making wool clothing, socks, and food. As to the cultural life of Sliven town and region, the dramatic theater is one of the main venues for various performing arts. There are many buildings in the city built in the National Revival Architecture style, including the Hadzhi Dimitur House-Museum. It is in the south western part of the town and shows visitors a complex of a native memorial home and an old traditional inn. The Dobry Chintulov Memorial House Museum is on the North side of Sliven; it was the home of the Bulgarian revival teacher and poet Dobry Chintulov. The city's main theater is located at the main city square. It is named after the Sliven native Stefan Kirov who was a prominent actor and director. The region currently includes 49 municipalities, some of which are Blatets, Bozhevtsi, Byala, Gavrailovo, Izgrev, Kaloyanovo, Kermen, Krushare, Staro Selo, Vaglen, etc.