Serious road bikers ride a fine line between simple masochism and insanity. Colorado hosts several full-day rides for the certifiable (the Triple Bypass, or Denver to Aspen), but if you are simply looking for a three-hour (or so) ride that will cause you acute pain, this one can't be beat. Begin at Chatfield State Park on South Wadsworth Boulevard. Head west into the foothills on Deer Creek Canyon Road. Turn left at Phillipsburg (which consists of an abandoned gas station). The road starts out easy enough, but soon turns into a series of killer switchbacks, climbing up what will seem to you like a sheer cliff. When you reach the top of this, you're not even close to done. Stay straight as the road turns into Pleasant Park Road. This climbs steadily (and, apparently, forever) into Conifer. From there it's finally all downhill: Barrel down Route 73, fly down North Turkey Creek Road to South Turkey Creek Road, and complete the vicious circle with a left turn back onto Deer Creek Canyon Road.