Summiting Longs Peak via the Keyhole Route is a rite of passage for Colorado hikers, though not an adventure to be taken lightly. The trail traverses Class 3 terrain, so you must have a strong stomach for exposure and be well prepared for emergencies. On top of that, this out-and-back trail is 14.5 miles long and requires route-finding along narrow ledges where no obvious trail exists. Most people begin the trek in the dark, hitting the trailhead at 3 or 4 a.m., as it can take between ten and twelve hours to complete. Needless to say, this shouldn't be anyone's first fourteener, but it's a worthy challenge for those who are up to it.
14ers.com