The North Face Endurance Challenge 50 mile run Madison, WI

An ideal course layout for elite speedsters and those taking their first strides in the world of trail ultrarunning, the Endurance Challenge Madison course is run-able from start to finish, provided that you’ve trained hard enough. Located 60 miles east/southeast of Madison, in the southern reaches of picturesque Kettle Moraine State Park, a large portion of the course takes place on the renowned Ice Age Trail.
http://www2.thenorthface.com/endurancechallenge/races/2009/wi/index.html
The forested area, massaged by monstrous glaciers many millennia ago, contains wake-up-call hill climbs of 200-300 feet and enough undulating terrain to challenge even those granite-legged mountain runners. Overall, the soft, forgiving course is 80% singletrack, with slightly wider, equestrian sections sprinkled in between. This is the least technical of all the Endurance Challenge courses.