From the west (Portland) or the east (Boise), you need to take I-84 to LaGrande, OR exit 261. (If, however, you are coming from the north - Spokane - you can take Highway 3 down to Enterprise, OR. Turn left onto Highway 82 there and follow it about 6 miles to Joseph, OR.) Take Highway 82 from there east about 71 miles to the town of Joseph, OR. Follow signs around Wallowa Lake to the Wallowa Lake campground. At the Wallowa Lake Lodge, turn left at the sign for the Wallowa Lake Trailhead and go maybe a mile to road's end and the trailhead.
From here it's a 2.8 mile hike in to the Ice Lake Trail. The trail stays to the left (east) of the river/creek. Once you reach the Ice Lake Trail, it crosses over and begins switchbacking up for 5.1 miles. The first couple are through meadows and come back and forth to a creek with neat waterfalls. There's a great spot on some rocks near the water for a break after the first few switchbacks. You'll pass a large tree blowdown that look to be from some avalanche at some point in the past although I am not positive on that.
Once you get to Ice Lake, there are some nice camping spots on the east and south side of the lake.
From Ice Lake, follow the trail around the north side of the lake which leads to the northwest corner. There is a trail, faint at times, that heads up northwest. It changes to the west and angles then southwest towards a large red ridge. It climbs the red ridge until you hit the white/grey face. From here you can traverse up to the left or scramble straight up to hit the summit ridge, turn left and walk easily to the true summit.
You can descend the same way or, as I did, walk the ridge to the north to the peak between Matterhorn and Sacajawea, traverse down the ridge heading east towards the Hurwal Divide until you hit a large scree field that you can plunge step down and save a lot of time. Once you hit the end of the scree, angle to the right and follow the streams down back to the trail.
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