Dam on Elk Lake, Itasca State Park, ca. 1940.

Fort Snelling. Oil-on-canvas painting by Alexis Jean Fournier, 1888.

Aerial view of St Peter State Hospital (St. Peter, Minnesota), April 13, 1954. Photo by the Minneapolis Star Journal–Tribune.

Employees of the St. Peter State Hospital (St. Peter, Minnesota) cutting ice on the Minnesota River, next to the hospital, January 1940.

The intersection of the Minnesota and Mississippi Rivers (Bdote), including Fort Snelling and Pike Island (Wita Tanka). The Sibley Historic Site is in the center foreground. Oil-on-canvas painting by Edward Kirkbride Thomas, ca. 1840.

Ruins of the Walker, Judd & Veazie saw mill at Marine Mill (Marine on St. Croix), May 1, 1909.

A waterfall and stream at the Marine Mills historic site at Marine on St. Croix, ca. 2010s. Photograph by Minnesota Historical Society.

Ruins of the mill operated by the Marine Lumber Company at Marine Mills (Marine on St. Croix) between 1839 and 1895. Photograph by John Cross for the Minnesota Historical Society, ca. 2010s.

Ruins of the mill operated by the Marine Lumber Company at Marine Mills (Marine on St. Croix) between 1839 and 1895. Photograph by Wikimedia Commons user MacGhiever, June 8, 2008. GNU Free Documentation License.

The headwaters of the Mississippi River at Lake Itasca. Photograph by Randen Pederson, June 2, 2010. CC BY-SA 2.0