Mount St. Helens National Volcanic Monument: Ape Canyon

Traverse the eastern flanks of the most active volcano in the Cascades on this 11.3-mile trek in Mount St. Helens National Volcanic Monument.
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You’ll link wildflower fields, pumice-covered plains, and boulder-size lava bombs in Mount St. Helens National Monument on this 11.3-mile dayhike. The trail begins from the small turnout just west of the Lava Canyon parking area and climbs northwest along the mile-wide lahar—a river of mud, rock, and volcanic debris—that flowed down the southeast face of St. Helens.
After a steady ascent through maple and alder, the forest transitions to hemlock and old-growth fir. Look through intermittent gaps in the trees to see the towering east rim of Mount St. Helens. (In late spring and summer, the shady trail is ablaze with a menagerie of wildflowers: penstemon, lupine, paintbrush, bunchberry, queen’s cup, and anemone.)
Near mile 2.5, the trail crests a ridgetop, revealing views in every direction: Ape Canyon far below, Mount Adams towering to the east, and Mount Rainier looming over Pumice Butte to the north. Less than two miles later, leave the cover of forest behind and enter the blast zone at the head of Ape Canyon, a pinched gorge with 100-foot-high walls. At mile 4.4, the trail ends at a junction with the Loowit Trail. Turn right and continue on Loowit Trail, traversing the stark Plains of Abraham, to a natural spring that creates a lush, wildflower-filled meadow.
Continue half a mile farther through a section of pumice desert to an area littered with giant lava bombs (volcanic boulders blasted from the volcano). Turn around and follow the same route back to the trailhead. (Optional: To add mileage, continue another 5 miles to the Windy Ridge viewpoint.)
Note: This trail is a popular mountain biking route. Be aware of oncoming bikers.

-Mapped by Eli Boschetto, Bosco Mountain Photo



MAPS USGS quads: Smith Creek Butte and Mt. Saint Helens ($8 each,

GUIDEBOOK Mt. St. Helens: A Guide to Exploring the Great Outdoors, by Fred Barstad ($16,

PERMITS Northwest Forest Pass required ($5 per day;

CONDITIONS For closures, snow levels, and trail work, check For current weather, check

CONTACT 42218 N.E. Yale Bridge Rd., Amboy, WA 98601, (360) 449-7800,

Synthetic T-shirt
Synthetic shorts or pants
Synthetic undies
Wool hiking socks
Hiking shoes or boots
Sunscreen (SPF 15+)

Midweight synthetic or fleece long-sleeve top
Wool or fleece hat
Waterproof/breathable jacket and pants
Map, compass, GPS unit
Water containers and water treatment
First-aid kit
Extra food and snacks
Firestarting kit
Lighweight gloves
Extra pair of socks (optional)
TP and trowel


1010 Atlantic Ave.
Woodland, WA
(360) 225-8475

9700 NE Highway 99
Vancouver, WA
(360) 576-9176

1303 NW Lovejoy St.
Portland, OR
(503) 205-6746

16842 Lewis River Rd.
Cougar, WA
(360) 238-5228

426 SE Grand Ave.
Portland, OR
(503) 233-0706

915 SE Hawthorne Blvd.
Portland, OR
(503) 236-355

611 Goerig St.
Woodland, WA
(360) 225-7753

Trail Facts

  • Distance: 18.2



Location: 46.1654, -122.092267

The trailhead is located in a small parking area just before the turnaround at Lava Canyon.


Location: 46.165551, -122.093897

View the mile-wide lahar (a mudflow of volcanic fragments) that covers down the southeast flank of Mount St. Helens.


Location: 46.167795, -122.09939

A short spur leads to a lookout over the lahar and a spectacular view of Mount St. Helens.


Location: 46.190583, -122.12145

Near mile 3.5, you'll start to see views of Mt. Adams and Mt. Rainier.


Location: 46.192217, -122.124217

A small campsite with fire ring is located just above the trail on the left (west).


Location: 46.19235, -122.12765

Look for spectacular views of Ape Canyon, Mt. Adams and Mt. Rainier.


Location: 46.195369, -122.132993

Stand at the edge of the 100-foot slot at the head of Ape Canyon for tremendous views.


Location: 46.195681, -122.134902

Turn right at the junction with the Loowit Trail. It's 0.8 mile to the natural spring.


Location: 46.20025, -122.13755

Connect the large pyramids of rocks that mark the path through the Plains of Abraham.


Location: 46.20033, -122.134452

Pass a miniature oasis filled with wildflowers at the brink of a towering cliff in the stark pumice plains.


Location: 46.20535, -122.136983

Giant lava bombs are scattered around the area; they look similar to the the erratics left by passing glaciers.


Location: 46.206062, -122.137177

A river of rocks at the 5.6-mile point marks the hike's turnaround point. To add mileage, continue on to Windy Ridge.


Location: 46.200359, -122.13413

A natural spring creates a miniature oasis in the barren Plains of Abraham. In summer look for large patches of lupine and paintbrush. © Eli Boschetto

Ape Canyon Trailhead

Location: 46.165387, -122.09188

Descend into second-growth maple and alder forest, en route to bigger, higher views. © Eli Boschetto

Lahar View

Location: 46.165625, -122.095613

The mile-wide mud and rock lahar that wiped out forest on the southeast side of Mount St. Helens. © Eli Boschetto


Location: 46.171866, -122.097931

After 1.2 miles, the forest transitions to hemlock and fir old-growth. © Eli Boschetto

Mt. Hood View

Location: 46.17726, -122.104197

From this ridge, look south for views of Oregon's Mt. Hood. © Eli Boschetto

Crater Rim

Location: 46.182623, -122.109346

Get peeks of the rim of Mount St. Helens. © Eli Boschetto

Mt. Adams

Location: 46.189814, -122.120848

Higher on the ridge, views start to open to the east showcasing the 12,276-foot Mt. Adams. © Eli Boschetto

Mt. Rainier

Location: 46.19118, -122.122736

To the north, spot views of the top of 14,411-foot Mt. Rainier beyond Pumice Butte. © Eli Boschetto


Location: 46.191789, -122.123165

A small campsite with fire ring just off the trail. © Eli Boschetto

Pumice Butte

Location: 46.192903, -122.128229

The colorful blast-scoured walls at the head of Ape Canyon. © Eli Boschetto

Trail View

Location: 46.193735, -122.130547

Higher up, the trail begins to open to grander views of Mount St. Helens. © Eli Boschetto

At the Brink

Location: 46.195191, -122.132649

View from the edge of the 100-foot rock wall slot into Ape Canyon. © Eli Boschetto


Location: 46.19528, -122.13398

The slot that funneled the 1980 mudflows down into Ape Canyon. Mt. Adams in the background. © Eli Boschetto

Loowit Trail

Location: 46.195666, -122.134559

Turn right (north) at this junction to explore the Plains of Abraham. © Eli Boschetto

Pumice Trail

Location: 46.198874, -122.1384

Hike over a small ridge to the natural spring and the espansive Plains of Abraham. © Eli Boschetto

Volcano Cairn

Location: 46.200315, -122.13722

Large cairns mark the path through the Plains of Abraham. Mt. Adams in the distance. © Eli Boschetto

Ape Canyon

Location: 46.200775, -122.134323

Another precipice view down into Ape Canyon. Mt. Adams in the distance. © Eli Boschetto

Lava Bomb

Location: 46.205423, -122.136641

Blasted from the mountain during the 1980 eruption, large lava bombs litter the area. © Eli Boschetto