Rocky Mountain National Park: Lily Lake to Sprague Lake Loop

Traverse exposed ridgelines and thick pine forests for postcard views of Rocky Mountain National Park on this 20.6-mile lollipop loop.

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This all-day loop on the park’s east side cruises 3 miles from Lily Lake to Stormy Pass before dipping south toward an abandoned mine and rounding the eastern slope of Longs Peak. The long climb toward treeline continues through alpine meadows and is interrupted with viewpoints of the Colorado plains and Long Peak’s east face. Watch for elk—and signs of approaching thunder storms—as the trail approaches mile 8.6 and the route’s high point at Granite Pass. You’ll skirt a backcountry campsite near mile 12 that’s located before the a rugged downhill section to the bottom of the Boulder Brook Trail. There is another 1,400 feet of climbing from the flats near Sprauge Lake to Storm Pass where you’ll close the 14-mile loop.

Note: The threat of lightning looms most of the summer and can force you to lower elevations by mid-day. If you get a late start, consider taking off from the Longs Peak Trailhead to hike the highest elevations first and stay below treeline in the later part of the day.

INFO For information on permits, current trail and camp conditions, and wilderness guidelines, go to

PERMIT A wilderness permit is required for all overnight camping in the backcountry. Reservations accepted ($20 administrative fee for permits during peak season).

CONTACT Rocky Mountain National Park, (970) 586-1206;

-Mapped by Tim Shisler


Trail Facts

  • Distance: 33.2



Location: 40.306596, -105.537844

From the parking lot, follow the Storm Pass Trail toward Estes Cone. The path skirts Lily Lake before veering south towards Longs Peak.


Location: 40.304823, -105.540172

Bear left at Y-junction and turn downhill toward Aspen Brook.


Location: 40.300574, -105.545418

Go straight at 4-way junction and continue along Storm Pass Trail. You’ll cross a bridge and begin climbing towards Estes Cone.


Location: 40.292952, -105.573587

This route’s clockwise, 14.6-mile loop begins with a left turn at the 4-way junction near mile 3. The trail drops and crosses several small streams heading toward the Longs Peak Trailhead.


Location: 40.286974, -105.564741

Turn right at 3-way junction with Eugenia Mine Trail.


Location: 40.286652, -105.56811

There is a campsite on either side of the trail and a privy at the Moore Park backcountry campground area just before the mine.


Location: 40.284076, -105.571876

You’ll cross intermittent Inn Brook before reaching an interpretive sign and ruins of an old well at the Eugenia Mine site where the trail opens up.


Location: 40.275086, -105.564255

This junction is just 0.5 mile from an alternative access point: the Longs Peak Trailhead. Turn right at T-junction onto the East Longs Peak Trail to continue the loop.


Location: 40.272812, -105.56985

There are 6 backcountry campsites and a pit toilet at Goblins Forest Campground on the south side of the trail.


Location: 40.273428, -105.580006

Cross Larkspur Creek and continue climbing above treeline. If you got a late start, or see storm clouds approaching, consider turning around, this route is exposed and above treeline for the next several miles.


Location: 40.270751, -105.584278

Bear left at the Y-junction and ascend the Mills Moraine on the main trail.


Location: 40.265626, -105.592561

This 3-way junction is a good resting spot. There’s a privy to the left and a well-marked trail heading toward Columbine Falls and Chasm Lake. Next: Turn right and continue up the rocky trail toward Granite Pass.


Location: 40.27432, -105.605425

Turn right at the 3-way junction near the pass and continue along the ridgeline of the North Longs Peak Trail. Look for elk and dramatic 50-mile views before dipping back into the trees.


Location: 40.287735, -105.612699

Near mile 11.4, Boulder Brook’s reliable flow is usually adequate for refilling water bottles (treat water before drinking).


Location: 40.289085, -105.616937

Turn right at this 3-way onto the Boulder Brook Trail. The trail narrows quickly and follows an old stream bed littered with lose rocks, deep ruts, and exposed roots.


Location: 40.291974, -105.617441

Bypass access trails leading to Boulder Brook campsites #1 and #2.


Location: 40.305696, -105.617042

Alongside Boulder Brook, expect dense aspen and lush vegetation that offer cool temperatures and glowing autumn colors.


Location: 40.316749, -105.615746

At this mile 13.7 junction, turn right and begin a long steady climb toward Storm Pass.


Location: 40.314876, -105.612023

Turn right at Y-junction onto Storm Pass Trail. Ahead, stay right at the 3-way junction in 0.6 mile to bypass East Portal bound trails.


Location: 40.307285, -105.600072

The upper reaches of the Wind River are generally reliable. Depending on the time of year, this might be the last available water before Storm Pass.


Location: 40.296042, -105.582961

Bear left at this clearing to continue ascent. You’ll close the loop at the 4-way junction atop the pass and just below Estes Cone.


Location: 40.305713, -105.538444

Getting an early start on this hike will give you time to finish before afternoon storms roll in and provide spectacular light.


Location: 40.30352, -105.550075

Longs Peak

Location: 40.291442, -105.568292

Look left for stunning views of Longs Peak.


Location: 40.270685, -105.583077

This popular and well-maintained trail system is signed and easy to follow.

Longs Peak East Face

Location: 40.265634, -105.592443

The Chasm Lake junction offers a spectacular view of Long’s East face.


Location: 40.281425, -105.600082

The alpine tundra below Longs Peak is a favorite lounging ground for elk.


Location: 40.297727, -105.617151

The pine and spruce-fir forests below treeline are occasionally interrupted by open, flower-filled meadows.


Location: 40.314221, -105.616722

In the lower reaches of the trail and alongside streams, you can also expect to see aspen groves.

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