There are many spectacular ways to summit Long’s Peak, and this description highlights the “standard” Keyhole Route. The route has two sides to it, a long approach with a little scramble to the keyhole, and from the keyhole to the summit which is rated as a Class 3 Grade 3 scramble/climb.
The standard route on Longs Peak is called the Keyhole route and it is usually done in one very long day. It is the route described below.
From the East Longs Peak trailhead follow the well maintained trail through pine forests. You reach a trail junction to Eugenia Mine Trail/Storm Pass after 0.45 miles. Continue straight along the East Longs Peak trail as it turns southwest through dense forest, gaining elevation through steep switchbacks. As the trail turns west, you pass through Goblins Forest, 1.1 miles in, and cross small creeks before climbing more switchbacks. As you approach treeline, you cross beautiful Alpine Brook on a well maintained footbridge, 1.85 miles in.
Leaving Alpine Brook the trail travels south through krummholtz and provides beautiful views of Twin Sisters Peaks to the east. The trail eventually leaves the low growth stands of krummholtz behind and enters alpine tundra, providing spectacular views of Longs Peak Diamond, a 1,000′ sheer cliff. The trail moderately climbs until it reaches Jims Grove Trail Junction, and then turns southwest along the basin until it arrives at Mills Moraine.
Here, there is a trail junction with Chasm Lake 3.25 miles in. Continue to follow the the East Longs Peak trail as it turns northwest going around to the east of Mt Lady Washington, climbing to Granite Pass, 4.3 miles in. At a trail junction on Granite Pass, the North Longs Peak Trail merges from the north. Continue on the East Longs Peak trail as it swings southwest along switchbacks and eventually enters the Boulderfield at the base of Long’s north face, where the East Longs Peak trail ends at a campsite area 5.9 miles in.
From the end of the East Longs Peak trail, the next destination is the Keyhole (.4 miles) to the southwest across the Boulderfield. The Keyhole is a weakness in the ridge between Longs Peak and Storm Peak, providing the only non-technical passage to the west side of the mountain along this route.
Scramble across large granite boulders until close to the keyhole, where the last 100 yards become increasingly steep. The Keyhole is a striking rock feature with a large overhang and a rock shelter built along the southeast side. Stepping through the Keyhole is one of the major highlights of the trip. The spectacular Glacier Gorge with its beautiful lakes and 13,000′ peaks come into view along with a 3,000′ drop. The exposure feels big, and some decide that the Keyhole is far enough. Knowing when to stop is honored wisdom. The way forward from here is much more rugged and dangerous than what has been encountered so far, and marked only with bullseyes.