Rocky Mountain National Park

Alluvial Fan

FamiliesPhotographersGeology Enthusiasts
0.8 mi Distance
Varies Estimated Time
roundtrip Trail Type

What to Expect

This is less a hike and more a geological show-and-tell. From the West Alluvial Fan parking area, you'll walk barely half a mile to witness the dramatic aftermath of the 1982 Lawn Lake Dam failure — a catastrophic flood that reshaped this entire drainage in a single morning. The trail crosses a sprawling fan of boulders, gravel, and debris deposited by the flood, with Roaring River tumbling through the wreckage. The terrain is rocky and uneven, with informal paths weaving between car-sized boulders. In early summer, snowmelt turns the cascade into a legitimate waterfall worth photographing. The whole thing feels like nature's construction site — raw, exposed, and surprisingly powerful for such a short walk. Perfect for families with curious kids, geology nerds, and anyone who wants a big payoff without breaking a sweat.
FamiliesPhotographersGeology EnthusiastsWaterfall LoversQuick Stops

Safety Advisory

The rocks near the water are deceptively slick, especially when wet from spray. Several visitors have been injured slipping on the boulders closest to the cascade — keep kids within arm's reach near the water's edge.

This area sits at roughly 8,500 feet. If you just drove up from the Front Range, even this short walk can leave you winded. Take it easy if you're not yet acclimated.

Trail Details

Distance 0.8 miles round-trip
Estimated Time Varies
Trail Type roundtrip
Pets Not allowed
Season Year-round
Trailhead Alluvial Fan

Pro Tips

Trail Tip

Visit in late May through June when snowmelt is at its peak — the cascade is at its most dramatic and photogenic. By August, it can slow to a trickle in dry years.

Trail Tip

The 'trail' is largely informal paths across the boulder field. Wear shoes with decent grip rather than sandals — the rocks are uneven and can be slippery near the water.

Trail Tip

Walk past where most people stop at the first cascade view and scramble upstream along the boulder field for a less crowded vantage point where you can see the full scope of the alluvial fan spreading below you.

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