Climbing magazine reports that early this week Tommy Caldwell redpointed his longtime project at the limestone crag called Fortress of Solitude near Rifle, Colorado. The 120-foot overhanging linehad a working title of Flex Luthor, is 100 feet to the right of Caldwell´;s other sport-climbing benchmark, Kryptonite (5.14c/d) – about F8c+/9a.So how hard is his new route? “It´s the hardest thing I´ve ever done,” says Caldwell, who prefers not to give it a solid grade, but does allow that, “it´s definitely harder than Kryptonite.” Needless to say, it´s likely one of – if not the – hardest sport climb in America. Look for a full report and stunning photos of the route in Issue 221 of Climbing. Previously the hardest and best-known route (as opposed to boulder problem) was the 60m power-endurance fest Just Do It (5.14c) on the Monkey Face of Smith Rock, first climbed by Jibe Tribout. ( Source: Climbing magazine )