Approach this climb via the Stuart Lake Trailhead near Leavenworth. From downtown Leavenworth, turn left (south) on Icicle Creek Road, following it for 9.5 miles before making a left on road 7601. Follow this for just over 4 miles to the Stuart Lake Trailhead at 3,540 feet. Note: This road is not plowed in the spring, so expect to ski or hike in the last few miles if you are attempting this climb before approximately May 1st. In early season (usually before mid April) the road is often gated where it crosses Icicle Creek at Bridge Creek Campground.
Depart on the Stuart Lake Trailhead following Mountaineer Creek up the valley toward Stuart Lake. At 3 miles you will notice a sign indicating the trail for Colchuck Lake. Don't turn here. Stay on the Stuart Lake Trail for another .8 miles to a clearing. This will be your first view of the north face of Argonaut.
From this point, continue on the trail for approximately .2 miles more, then depart the trail heading due south through the timber. Move south until you encounter Mountaineer Creek again. Look for a log to cross the creek onto the east side (there are many). Follow the east side of the drainage of the creek to a point where it forks off into 3 sections. Here, you want to follow the east most branch which leads to an open clearing below the north face of Argonaut. At this point, head southeast up some steep avalanche prone snow slopes to obtain the entrance to the couloir.
The couloir is approximately 1,200 feet long varying in width from 50 feet down to 10 feet. It is mostly 35 degrees with a couple steeper sections of 40 to 45 degrees. In cold weather, after significant freeze/thaw, the couloir could be neve or ice. We encountered soft snow, which made the going easy. If the couloir is ice, it should be noted that there is ample rock protection on the rock walls or either side of the couloir.
At the top of the couloir, you have several choices. Your goal is to obtain the snow slopes which lead to the summit ridge. You will notice a prominent dihedral in the middle. This is the route I took. It was about 100 foot long of class 5 climbing up to 5.6. I freesoloed this in plastic boots. (not recommended for the faint at heart). Another option is some broken terrain to the right. Paul Klenke described this as mostly 4th class with one move of 5.6. I would recommend this option, unless you bring a rock rack. There might be a 4th class way up, but we didn't make an exhaustive search of the possibilities.
Getting to the Ridge
After getting to the snow slopes on the north side of the summit ridge, making a rising traverse towards the center of the summit ridge. Do NOT climb directly up to the ridge. This will put you above a large notch which will require rappeling into.
Ridge & Summit
After reaching the halfway point on the ridge, make your way towards the true summit tower (the west one) via traversing the crest of the ridge (class 3). As you approach the summit block pass through the cave made by the block standing on end, or pass it on the south (left) side. Look for a broken double crack system on the south side of the summit block about 12 feet high. Climb this (4th class) to reach the tallest point.
Follow your tracks back to the top of the technical rock pitch above the couloir. Now rappel 50 meters to the base of the rock section, or downclimb it (not recommended). At this point you have a few options.
1. Downclimb the Northeast Couloir
2. Traverse to the East Gully, downclimb it, traverse to the ridgeline between Argonaut and Colchuck, then downclimb some lower angle snow back into the basin.
3. Rappel down the rock sections into the basin on the east side of the peak. This is not a recommended option, since you would have to make your own rap stations.
This gear list is for non-icy conditions:
Crampons (may not need them)
Light rock rack
2 50 meter ropes (to rappel the 5th class)
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