The Kettle Moraine 100 is an ultramarathon held annually in early June in Kettle Moraine State Forest near La Grange, Walworth County, Wisconsin.
Runners registered for the 100-mile race may drop at the 100km finish.
The 100-mile course is run entirely on trails (except for a couple hundred feet of road crossings) and traverses the Ice Age Trail for about 65 miles.
The trail is about 80% wooded terrain with the rest meandering through gentle prairie or marsh areas.
Despite the low elevation, a roller coaster of hills amounts to a total altitude gain of approximately 8,800 feet.