For the more information about the air resources of the National Park Service, please visit http://www.nature.nps.gov/air/.
The largest natural lake bed in South Dakota, Lake Thompson contains a large undisturbed and unmanipulated marsh. The site is an outstanding waterfowl breeding and resting area.
Location: Kingsbury County, SD
Year designated: 1975
Please remember, National Natural Landmarks (NNLs) are not national parks. NNL status does not indicate public ownership, and many sites are not open for visitation.
Last Updated: June 28, 2012