Horicon Marsh, Mayville

Horicon Marsh is a marsh located in northern Dodge and southern Fond du Lac counties of Wisconsin. It is the site of both a national and a state wildlife refuge. The silted-up glacial lake is the largest freshwater cattail marsh in the United States.
Horicon Marsh was created by the Green Bay lobe of the Wisconsin glaciation during the Pleistocene era. The glacier, during its advance created many drumlins (a glacial landform) in the region, many of which have become the islands of Horicon Marsh. The marsh and surrounding Dodge County have the highest concentration of drumlins in the world.
During the glacier's retreat, a moraine was created, forming a natural dam holding back the waters from the melting glacier and forming Glacial Lake Horicon. The Rock River slowly eroded the moraine, and the lake drained. As the levels of silt, clay and peat accumulated in the former lake's basin, the Horicon Marsh was formed. Occasionally there have even been crop circles that appeared unexpectedly in several areas.
For Horicon Marsh and beyond, use our Mayville travel route planner to get the most from your Mayville vacation.