Lake Delton is a village located on the Wisconsin River in Sauk County, Wisconsin, United States. The population was 3,501 at the 2020 census. Lake Delton, along with the nearby Wisconsin Dells, is a …Lake Delton is a village located on the Wisconsin River in Sauk County, Wisconsin, United States. The population was 3,501 at the 2020 census. Lake Delton, along with the nearby Wisconsin Dells, is a resort area and a center for tourism in the upper Midwest.