The Trans Iowa Version 7 ran this past weekend. I had signed up for this a few years ago, but ended up not being able to go. A big-assed loop over gravel and crappier roads through the ruralness of Iowa, for over 300 miles, with a time limit. Seven runnings - some years not even a finisher, the weather is a humongous factor, along with having to ride through the night.
Check out a blow by blow account by one of its founders Guitar Ted here.