Marge Cline Whitewater Course runs through Bicentennial Riverfront Park in downtown Yorkville, Illinois, using a roughly 1,100-foot bypass channel that lets paddlers skip the portage around the Glen D. Palmer Dam on the Fox River. The channel drops almost six feet over its length, and the second drop on river right is the one locals point to for an actual surfable wave. It's open-use and free, built for novices and experienced paddlers alike, with a concrete path alongside so you can walk your board back upstream for another lap. There's no lifeguard on site, so bring your own PFD, and rentals are available nearby through the Yak Shack if you show up without a boat.