Parking
Start at the Carbon River Entrance; follow the Rain Forest Loop to its back, where the West Boundary Trail branches off.
Overview
About West Boundary Trail
Why go
- Rainforest canopy and a waterfall creek add variety to a hard climb.
- The ridge junction gives the route a clear turnaround.
Heads up
- Steep 2,800-foot climb and a slippery creek crossing.
West Boundary Trail is a strenuous 6-mile out-and-back from the back of the Rain Forest Loop to a high ridgeline junction with the Florence Peak Trail. The National Park Service lists about 2,800 feet of climbing and an average four-hour hike. Pick it for a hard climb through dense Carbon River forest; the reward is the ridge, not an open summit.
Parkwolf’s verdictIs this the hike for you?Map & elevation
The route
Loading the Mount Rainier map
Full mapElevation1,818–4,587 ft
Plan your hike
Before you go
Parking
Safety
7 active Mount Rainier alerts
- ClosureSR 165 bridge closed: no public access to Carbon River or Mowich LakeMentions Carbon River, referenced in this guideThe SR 165 Carbon River/Fairfax Bridge is closed to vehicles, bicycles, and pedestrians; there is no public access or alternate route to Carbon River or Mowich Lake.Official details
- ClosureWildfire closures in the northern parkGrand Park 2 and Wonderland Complex fire closures affect trails, backcountry camps, and Sunrise access; stay out of closed areas.Official details
The highest, rockiest slopes around here are a summer buffet for grizzly bears.
Mount Rainier Tour Guide
Your drive to West Boundary Trail, narrated.
Parkwolf is a GPS audio tour guide for Mount Rainier National Park. As you drive, it chimes in with what’s ahead: hidden gems, upcoming stops, history, geology, and wildlife, right through your car’s speakers.
See the Mount Rainier audio tourRecorded for this area
An Alder's Underground Helpers0:00 / 0:30
“Red alders can get a start on rocky river margins where many other trees struggle. Part of their advantage is underground.”
Plays near this trailhead in the Parkwolf Mount Rainier Tour Guide.
More stories near here in the app
- A Small Wren's Big Song
- Carbon River Ranger Station: The Farmhouse Desk
- The Bee That Shakes the Flower
- Tolmie's Botanical Journey
- 77 audio storiesacross Mount Rainier’s roads, triggered by GPS as you drive
- Wildlife heatmapsfor Mountain Goat, Black Bear, Wolverine, and 13 more
- Works offlinemaps, 99 trails, 87 places, and audio download before you lose signal
- CarPlay readysimple controls built for the drive
“Fantastic app with many points of information… It’s great to just turn on while you’re driving and it gives you an audio tour of the national Park. We love it!!!!”
Trail guide
Hiking West Boundary Trail
The ridge is the turnaroundBeyond the creek, the trail gets narrower, rockier, and rootier. Around 2.
Beyond the creek, the trail gets narrower, rockier, and rootier. Around 2.6 miles it skirts a slide of boulders and slide alder, then reaches the ridge and Florence Peak Trail junction at about 3 miles. Turn around there for the listed 6-mile total. The old Boundary line fades beyond the junction toward Tolmie Creek; it is not part of this hike.
A remnant of the old boundary routeThis is the surviving north-side section of the historic Boundary Trail, once used by park…
This is the surviving north-side section of the historic Boundary Trail, once used by park rangers to patrol the park perimeter. Beyond the Florence Peak junction, the old line fades toward Tolmie Creek, so this is a route to turn around on rather than a through-hike. High rainfall gives the Carbon River valley a temperate-rainforest feel, with cedar, hemlock, Sitka spruce, and Pacific silver fir along the climb.
Is this the hike for you?Start at the Carbon River Entrance, follow the short Rain Forest Loop to its back, and take the…
Start at the Carbon River Entrance, follow the short Rain Forest Loop to its back, and take the West Boundary fork. The tread climbs steadily on soft duff with roots and stone steps. At about 1.3 miles, an unnamed creek crosses tilted rock, with small waterfalls just above and below. If you want a shorter outing or the crossing feels unsafe, this is a sensible place to turn around.
Wildlife
Wildlife in Mount Rainier
466 sightingsMountain GoatMost seen around 6 AMSighting map
383 sightingsBlack BearMost seen around 7 PMSighting map
10 sightingsWolverineMost seen around 6 AMSighting map
58 sightingsElkMost seen around 6 AMSighting map
574 sightingsMule DeerMost seen around 6 AMSighting map
1,853 sightingsHoary MarmotMost seen around 6 AMSighting mapSighting maps show where each species has been reported across Mount Rainier. Wildlife moves, so no sighting is guaranteed.
