Caddo Lake is a 25,400-acre lake and bayou on the border between Texas and Louisiana, in northern Harrison County and southern Marion County in Texas and western Caddo Parish in Louisiana. The lake is named after the Southeastern culture of Native Americans called Caddoans or Caddo, who lived in the area until their expulsion in the 19th century. It is an internationally protected wetland under the Ramsar Convention and includes one of the largest flooded cypress forests in the United States. Caddo is one of Texas's few non-oxbow natural lakes and is the second-largest in the South; however, it was artificially altered by the addition of a dam in the 1900s.
Wildlife inhabiting Caddo Lake includes owls, snakes, frogs, waterfowl, bobcats, river otters, beavers, eagles, and alligators.