Dongting Lake, or Lake Dongting (Chinese: 洞庭湖; pinyin: Dòngtíng Hú; Wade–Giles: Tung-t'ing Hu) is a large, shallow lake in northeastern Hunan province, China. It is a flood basin of the Yangtze River (Chang Jiang). Hence the lake's size depends on the season. The provinces of Hubei and Hunan are named after their location relative to the lake: Hubei means "North of the Lake" and Hunan means "South of the Lake" in Chinese.
Dongting Lake is famous in Chinese culture as the place of origin of Dragon boat racing. It is the site of Junshan island, and is a home to the Finless Porpoise, which is endangered in China.
The Dongting Lake Bridge is a bridge with cable-stayed bridge section over Dongting Lake in northeastern Hunan Province, China. The bridge was completed in 2002 at a cost of $920 million. Cable-stayed section consists of three tower supporting a center spans of 310 m each and two identical side spans of 130 m each.
The Dongting Lake bridge is one of a handful of "next generation" bridges, worldwide, and includes cable dampers that use magnetorheological fluid which have the capability to change viscosity in response to an electromagnetic field. The bridge includes four lanes of traffic—two lanes in each direction.