The Yulong River is a small tributary of the larger Li River in Southeastern Gungxi Zhuang Province, and runs through the major city of Guilin to Yangshuo. The Yulong starts in Northern Yangshuo County near Litang and runs for over 35km through small villages of the Yulong River Valley, including Putao, Litang, Chaolong, Yima and Gaotian town, before emptying into the Li around the town of Ping Le. The Yulong is a shallow river of around 5 meters maximum depth and an average of 25 meters across. As it is not located near any industrial areas, it is clean enough for swimming, though some brownish surface foam is visible in eddys, likely the result of agrigultural runoff from local villages. Unlike the busy Li River, it has no motorized boat traffic and relies completely on bamboo rafts to ferry passengers down river. This has become a popular tourist activity, with passengers beginning their journey that the Yulong Bridge, a 600 year-old example of a classical Chinese stone arch style. The river just North of the Yulong brigde is also a natural swimming area, with clear pools and gentle currents.