The Key Hole Route is Longs Peak's most challenging and non-technical hiking route and is open for hikers and climbers for a short span of time during each summer. The route is eight miles long and a one-way hike that gains an elevation of approximately 4,850 feet. Opening in mid-July and closing in early to mid-September, the route is typically free from snow and ice during this time frame.
Reaching the summit and then getting off of the route before the common afternoon thunderstorms kick in is crucial and recommended by the park rangers. Typically hikers begin at the trailhead by 6 am to ensure the timely return. Also to ensure ample parking spaces an early morning arrival is necessary.
The terrain can be extremely rugged in areas and requires rock hopping, the use of hand-holds, and scrambling. Located just below the Key Hole Route, hikers can find the Agnes Vaille Shelter, which was a memorial that was built after Ms. Vaille died in 1925. Ms. Vaille was the first person to climb the Keyhole Route and through the notch during the winter.
The Keyhole mixes long stretches of open terrain with rocky climbs. Immediately after going beyond the Keyhole the hike becomes treacherous and safety precautions are necessary.