Mount Idaho Hiking Guide

Mount Idaho Trailhead, Parking & Camping

Besides the Borah Peak Trailhead, this is one of the more accessible Lost River trailheads. From Mackay, head northwest on US-93N for 15.2 miles. Turn right onto Elkhorn Creek Road. Continue up this rough road for just under a mile, keeping the creek to your left. Avoid the left turn about half a mile in that would take you north across the creek to the wrong side. Low-clearance vehicles can make it up fairly high on this road, but high ground clearance is likely needed to make it to the trailhead, which begins at the end of the road. No amenities at trailhead. 

West Ridge / Southwest Face Route Overview

Mount Idaho offers a full Lost River Range experience. The route begins near Elkhorn Creek, where water is available low on the mountain before the climb steepens dramatically. Higher up, the route moves through rough talus, broken chutes, and increasingly exposed ridge terrain. The upper mountain requires careful route-finding as hikers work toward the West Ridge and Southwest Face, where the terrain becomes more rugged and the scrambling more sustained.

Trailhead to Ridge

Take the small single-track path heading northeast from the trailhead as it travels above Elkhorn Creek. Within the first half mile, you will cross the creek twice, eventually ending up on its right (southern) side. Shortly after the second creek crossing, the trail becomes steeper, gaining about 500 feet in just over a quarter mile. The top of this incline (8,100ft) sees you leaving the sage and grass for thick pine trees and lava rock. For 1.25 miles, you will walk through the trees alongside the creek as it gains 1,150 feet. The trail can be tricky to follow as it moves through the pines, so keep an eye out for rock cairns.

At around 8,800 feet, about 1.6 miles into the hike, the trail will cross from the south side of the creek to the north. From this crossing, continue for a quarter mile until you reach the rock field at 9,250 feet. Head north up the rock field for about half a mile. This is a steep scramble that will require quite a bit of route finding. Scramble up the field toward the ridge to the right of a rock tower outcropping. At the top of this ridge (10,600ft), you will get an excellent look at Mount Idaho.

Ridge to Bottom of Chute

Follow a trail northeast across the talus field toward the saddle. You will come across the first of two rocky spines at the saddle on the West Ridge. This first spine, the longest of the two, is covered in incredibly sharp white rock, so gloves are highly recommended. The first half of the spine is a “choose your own path” type climb, though keep an eye out for rock cairns, as they may lead you to an eroded trail on the left (north) about midway up that allows you to bypass much of the sharp rock. Shortly after crossing the spine, you will see the second scramble at the end of a barren flat. Look for a small trail toward the right side of the scramble to help on the ascent.

The top of this second scramble, otherwise known in this book as the upper rest (11,140ft), makes for a great resting spot before beginning the last stretch of the climb. From the upper rest, continue northeast following cairns until you are below the cliffs of Mount Idaho’s West Face. Here the path will make a right (east) turn as you make your way below a series of intersecting rocky chutes. The trail ends at a large cairn pile, which signifies the point to turn uphill.

Chute to Summit

Ascending these steep talus and scree chutes sees you gaining 500 feet in under a quarter mile. There is no one correct way up this final stretch, though generally, you want to stay left of the visible path during this uphill section, as the path is a downhill scree trail. Use the large rocks and cliff walls for traction. The summit is easy to miss in favor of a false summit on the right, so keep left as you near the top. Once on top, you will get a spectacular view of Sacajawea Peak and Borah Peak to the north, Mount Corruption to the east, and White Cap Peak and Leatherman Peak to the south. 

Descent

The route down the mountain is slightly different than the ascent. You will retrace your steps down the summit, past the upper rest, and across the two scramble sections. Once you reach the saddle talus field at around 10,770 feet, turn left down the scree into the bowl instead of walking over to the ridge. This option requires a bit of bushwhacking, but it is easier than downclimbing the rockfield you climbed up during the ascent. Descend the steep scree until you enter the forested bowl. From there, head southwest, reconnect with the trail, and follow the regular route back down.

Frequently Asked Questions

How Hard is Mount Idaho?

Mount Idaho is rated Class 3, but it is not a casual scramble. Much of the difficulty comes from the looseness of the terrain and the amount of route-finding required. This is a mountain where poor line choice can quickly make the climb feel more serious. Strong hikers with prior scrambling experience will find it rewarding, but inexperienced climbers may find the steep talus and exposed sections intimidating.

What Makes Mount Idaho Dangerous?

The biggest hazard on Mount Idaho is loose rock. The talus chutes are notoriously unstable, and rockfall is a real concern, especially if climbing near others. A helmet is strongly recommended. Unlike a peak with one short crux, Mount Idaho spreads its difficulty across a longer section of broken terrain, which means hikers need to stay alert for much of the climb.

Best Time to Hike

Mount Idaho is generally best climbed in summer and early fall, when the route is dry and free of lingering snow. Earlier in the season, snow can make the chutes and upper scrambling considerably more dangerous. Stable weather is important, especially since much of the upper route is exposed and slow-going.

Tips, Gear, and Common Mistakes

Carry enough water after leaving Elkhorn Creek, as reliable sources disappear higher on the route. A helmet is one of the most important pieces of gear on this mountain due to the amount of loose rock. One common mistake is underestimating how slow travel can become once the scrambling starts. Another is drifting into dangerous rock-filled chutes instead of staying on the most efficient line. Careful route choices make a big difference here.

Should You Hike Mount Idaho?

Mount Idaho is best suited for hikers who want a rugged, less-traveled Lost River summit and are comfortable with loose Class 3 terrain. It is not the most beginner-friendly Idaho 12er, but for those with solid scrambling experience, it delivers a memorable climb with excellent views and a more adventurous feel than some of the better-known peaks.