Sliven, in the Northern Thrace region of southeastern Bulgaria, is the eighth largest city in Bulgaria, with nearly 90,000 people as of 2011. The city sits below the famous rocky massif, Sinite Kamani (The Blue Rocks), and is known for being one of the windiest cities in Bulgaria. Surrounded by natural splendor, the three rivers--Asenokvska, Novoselska, and Manastirska-- converge in the city. The city is famous for the Bulgarian Haiduts who fought against the Ottoman Turks during the 19th century.