Lake Agassiz was a large glacial lake in central North America. Fed by glacial meltwater at the end of the last glacial period, its area was larger than all of the modern Great Lakes combined, although its mean depth was not as great as that of many major lakes today. First postulated in 1823 by William H. Keating, it was named by Warren Upham in 1879 after Louis Agassiz, when Upham recognized that the lake was formed by glacial action.

Watertown is a city in and the county seat of Codington County, South Dakota, United States. Watertown is home to the Redlin Art Center which houses many of the original art works produced by Terry Redlin, one of America's most popular wildlife artists. Watertown is located between Pelican Lake and Lake Kampeska, from which Redlin derived inspiration for his artwork. The population was 21,482 at the 2010 census, making Watertown the fifth largest city in South Dakota. It is also the principal city of the Watertown Micropolitan Statistical Area, which includes all of Codington and Hamlin counties. Watertown also is home to the Bramble Park Zoo. Watertown's residential real estate is considered the most expensive in South Dakota for cities of its size; the median price for a home in Watertown is approximately $200,000.

Garretson is a city in Minnehaha County, South Dakota, United States. The city had a population of 1,166 at the 2010 census.

Marshall is a city in Lyon County, Minnesota, United States. The population was 13,680 at the 2010 census. Marshall is a regional center in southwest Minnesota, and the county seat of Lyon County. It is the headquarters of the Schwan Food Company and the home of Southwest Minnesota State University.