Three Prong Mountain

Page Type Page Type: Mountain/Rock
Location Lat/Lon: 45.77290°N / 114.9269°W
Additional Information County: Idaho
Additional Information Elevation: 8182 ft / 2494 m
Sign the Climber's Log


Shadow On Three Prong MountainThe south side of Three Prong Mountain

Summit of Three Prong MountainThe summit
Point 7,820 Near Three Prong MountainPoint 7,820
The Last Bit of Ridge to Three ProngSummit area
Point 8,026Point 8,026
The Summit RidgeSummit ridge
North Ridge Point, 8,109Point 8,109
Southwest Aspect of Three Prong MountainSouthwest face
Point 8,136, South of Three ProngPoint 8,136
Northeast BowlNortheast bowl
Rocks of Point 8,136Point 8,136 rocks

Three Prong Mountain is the highpoint in a cluster of closely packed mountains, ridge points and glacial cirques at the north end of the peculiar ridge that runs north and south, perpendicularly crossing the main Salmon/Clearwater divide. Most major geographic features in the Clearwater and northern Salmon basins run east and west. This ridge system runs over 20 miles and has several points over 8,000 feet. It reflects the climatic transition from the northern maritime flows of the Clearwater Basin and the southern continental climate of the Salmon Basin through vegetation changes over the length of the ridge. The 8,182 foot mountain has 862 feet of prominence and gets its name from three outcrops protruding from the summit ridge.

The area is part of the southern Clearwater Mountains, which forms the highest part of the expansive Clearwater Mountains of north central Idaho. The southern Clearwater Mountains forms much of the divide between the Clearwater and Salmon basins and contains many peaks between 8,000 and 9,000 feet that rise above the low elevation canyons of the Salmon and Selway rivers. Three Prong Mountain and its close neighbors form the dividing point between Lynx and Eagle creeks (both main forks of Running Creek), Burnt Knob Creek and the headwaters of Bargamin Creek, which is one of the principle tributaries to the Salmon River. Generally it rises 2,000 to 4,000 feet above various points in these basins. The west side is very steep, but studded with an open subalpine forest of stunted trees. The east side is formed by sheer cliffs dropping nearly 400 feet to a steep talus slope and snow patches that last most of the year. There are three small subalpine lakes on the flanks of Three Prong Mountain, all of which are nameless.

While the area is beautiful, wildfires have diminished the appeal somewhat leaving much of the area a standing dead forest. Fires are not generally suppressed in the nearby Selway Bitterroot Wilderness and since these adjacent areas are quite primitive and roadless, fires are often minimally suppressed here as well. After several years of severe burn conditions, there isn’t much left to burn with tens of thousands of acres impacted.

While the trailhead vicinity near Burnt Knob is heavily used by a variety of recreationalists, it is very easy to find isolation on the ridge north to Three Prong. The first part of the hike out the ridge between Burn Knob and Three Prong Mountain is on the Idaho Centennial Trail (see map). Very few people venture far beyond the trailhead/Burnt Knob area and the trails are vanishing due to wildfires, and lack of use and maintenance. However, hunters with stock will use the area in the fall so wear orange and be aware. The area also has a good wolf population so consider leaving the dogs home.

Getting There

The RouteLooking north over the route from the trailhead

The Drive

Scorched TrailScorched trail
Older Burned SectionOlder burned trail
Rare Unburned Portion of TrailRare unburned trail

From Highway 95, turn east into Grangeville and continue on main street (Highway 13) for a long mile to the east edge of town. Town ends abruptly at the intersection of Highway 13 and the Mt. Idaho Grade road. From this intersection turn south (right) on the Mt. Idaho Grade road. After driving approximately 0.7 miles take the curve to the left at the drive-in theater (the curve is the main road). Continue on through the cluster of houses known as Mt. Idaho and soon the road will descend into the deep canyon of the South Fork of the Clearwater River. The road hits the canyon bottom and Highway 14 joins from the left, 9 miles after the theater curve.

At the bottom of the grade continue straight for 38 miles to the Red River Road. Turn right and continue up Red River for about 14 more miles to Red River Ranger Station. Turn right (keeping on the pavement) and go through the Ranger Station for 0.4 mile to the Montana Road, Forest Service Road 468 (also known as the Magruder Road or the Nez Perce Trail Road). Turn left off the pavement on this road and continue 19 miles to the junction of road 285 to Green Mountain. Keep right and go almost 11 miles to the Burnt Knob turnoff. This road is about 5.5 miles beyond the Poet Creek Campground in the bottom of Bargamin Creek and 1.2 miles before Dry Saddle. The trailhead is a little over a mile up the Burnt Knob road. The first part of this road is very rugged and unless one has a 4WD with high clearance, they should seriously consider walking from the 468 road. From Grangeville, the total drive will take approximately three hours depending upon traffic and driving conditions.

Caution should be taken on much of this route. For several miles on Highway 14 just east of the base of Mount Idaho Grade, the road is very narrow and twisted. Watch the speed and stay on the right side of the road and hope the oncoming traffic (largely composed of RVs and logging trucks) does as well. The shoulder is falling into the river on this already narrow road and in some places even the white strip is going, leaving absolutely no space between you and the river. On the mountainous portion, the road is very narrow and steep from a little beyond the junction with Road 285, which is about 19 miles in from the pavement, to Poet Creek. If you meet another vehicle, one of you could be backing up a long way.

Part of the adventure of going into this part of Idaho is driving along the South Fork Clearwater River. This small, but beautiful river has a steep grade over endless boulders of class III, IV, and V whitewater in the spring. About 10-15 miles upstream the canyon tightens into a spectacular gorge with miles of technical climbing that is never climbed. Low elevation mountain goats are not an uncommon site here on large granite walls. All is especially beautiful in the fall when the larch and broadleaf trees lining the rocky stream turn gold. The river also supports good runs of steelhead and Chinook salmon, which can be seen jumping some of the small waterfalls during the appropriate season.
South Route OverviewLooking over the south half of the route from the north

The Hike

Nearing the Mid-pointNearing mid-way
North Portion of the RouteNorthern summit cluster
Yellow Buckwheat on Three ProngYellow buckwheat on the southern prong
Last Stretch of RidgeLast bit of ridge between point 8,136 and Three Prong

From the trailhead on Burnt Knob, Three Prong Mountain is approximately a seven mile hike one way. The trail starts off well maintained and easy to follow due to all the traffic to the three Burnt Knob Lakes. It is easy to follow for much of the way beyond the lake basin though the fires have removed all vegetation and turned the ground to ash so in places there really isn’t much of a readable path. About two thirds of the way in the trail completely vanishes, but the ridge is broad and gentle and there is no question as to where to go. About halfway in the historic Southern Nez Perce Trail route is crossed, but due to little use and recent hot-burning fire, there is no trace of it to be found on the ridge.

Once the trail is gone, it’s simple to just follow the ridgeline. This has some unnecessary climbing to get up over point 7,820, which is easy to avoid by cutting across the east slope of the point, and then contour around the south aspect of the ridge below point 8,026, while gradually climbing to the broad point 8,136. From here Three Prong is an easy, mostly level ridgeline hike through a nice open subalpine fir/whitebark pine forest carpeted with a heavy blanket of wildflowers. The yellow buckwheat on the rocky outcrops is especially beautiful.
North End of RouteHigh points on the north end of the route from Three Prong

Red Tape

None. Three Prong Mountain is not in a designated wilderness area, but it is roadless and adjacent wilderness area so shares many of the same management limitations. If you have other plans in the general area be aware of where the wilderness boundaries are.


Unnamed Lake Southwest of Three ProngUnnamed lake at southwest foot of Three Prong Mountain
Unnamed Lake South of Three ProngUnnamed lake, point 8,136
Dry SaddleDry Saddle
Source of Bargamin CreekUnnamed lake close up

There are several primitive camping opportunities in the area. There are designated campgrounds at Poet Creek and Dry Saddle. Neither has much in the way of services other than pit toilets and some places to park a vehicle and put out some tents. Water at Poet Creek comes from Poet Creek or Bargamin Creek, which join at the campground. There is no water at Dry Saddle.

With difficulty it is possible to drive to the summit of Burnt Knob and camp there. The lookout is unlocked so one could sleep inside is desired. There are flat spaces for a tent or to park a vehicle. Much of the forest in the area has burned, but the views of the lake basin below still make this a very scenic camping option. Just below the summit at the trailhead there are some good flat tent spots that would make a good camping spot as well. Another good option is to pack the short distance in to the Burnt Knob Lakes and camp by them under the impressive east wall of Burnt Knob. For backpackers there are many places to camp on the broad ridge out to Three Prong Mountain, though water is lacking for several miles. Adjacent the mountain itself there are two unnamed small mountain lakes that are nice settings for a camp. Be prepared to hike seven or eight miles into them. Finally there are several good pullouts for dispersed camping at a number of places along the road between the Selway River and Red River Ranger Station. But bring water because most are dry.

When To Climb

Rocky Mountain Paintbrush (Castilleja covilleana)Rocky Mountain paintbrush

Obviously the summer is the best time to reach this summit. The Montana Road is not cleared in the winter so it is impossible to get anywhere near the mountain during that season. At this high elevation come prepared for any kind of weather regardless of the time of year, even on days that seem warm in the morning. Storms can and often do blow up out of nowhere and can drop temperatures dramatically and bring rain or snow. It is possible to snowmobile along the Magruder Road, but it’s a long way to the Burnt Knob vicinity from the accessible ends of the road. Generally it’s a good rule to only snowmobile as far as you are willing to walk out. If this rule is followed, it is not possible to get close to the trailhead in the winter. And the mountain is several miles from the trailhead at Burnt Knob.

More Information and Current Conditions

Three Prong WildflowersThree Prong rock garden

Go to the mountain prepared for variable conditions. Weather and temperatures can vary dramatically between the canyons and the mountain. While it’s a relatively safe mountain with easy terrain, any trip this area should involve caution and good planning. It’s a very long day hike to the mountain and the trailhead is hours away from anywhere on a primitive road.

Before traveling the Magruder Road or for more information and current conditions in the vicinity, contact the Nez Perce National Forest or the Red River (Elk City) Ranger Station.

Nez Perce National Forest
104 Airport Road
Grangeville, ID 83530

Red River Ranger Station
Elk City Ranger Station
300 American River Road
Elk City, ID 83525

NOAA Forecast