The central region is considered the cradle of Central Asian nomadic civilizations, owing to its Orkhon Valley. This area has been continuously inhabited by various ancient peoples, namely the Huns, Uighurs, and Turks, since the 3rd century BC. At its peak, it was the capital city of the greatest Mongol Empire, Kharkhorin, and an important destination on the ancient Silk Road. In addition to the historical sights of the Orkhon Valley, Mongolia's heartland boasts many natural wonders to explore, including Terkhiin Tsagaan Lake, the Orkhon Waterfall, Tsenher Hot Springs, and Ugii Lake.