Isolation Traverse in a Day

Isolation Traverse in a Day

Eric and Duncan

May 22, 2021, 1:45am – 1:45am May 23

29 miles, 14kft gain

This spring I’ve been wanting to do one of the classic ski traverses in the cascades to mix things up a bit from my standard peakbagging trips. I would say the major classic ski traverses are Ptarmigan and Isolation. The Ptarmigan Traverse is unfortunately difficult to complete this year because the main exit point, the Downey Creek trail, is still closed from a fire last fall. But the Isolation traverse doesn’t have restrictions like that.

The Isolation Traverse starts at the Eldorado Trailhead on Cascade River Road and ends at the Pyramid Lake trailhead on Highway 20. Most of the ~29 mile route is above treeline on glaciers with amazing views of the cascades, and this kind of terrain lends itself well to a ski traverse. Most groups doing the traverse take two or three days, and go in the spring when days are long, avalanche hazard is low, crevasses are filled in, but snowline still extends pretty low.

I was excited to try to do the traverse in one push. This would mean not carrying heavy overnight gear and also sounded like a fun challenge. I read a report from Kyle M and friends skiing it in one push in 2020 and sounded like a fun trip. Duncan was also interested, and we planned to ski it Saturday.

Unfortunately this year the Cascade River Road is still gated at the park boundary

at milepost 18 due to a washout, and that adds two miles road walking to the approach. It would be great to bike that section, but since we were doing the traverse that would mean we would have to go back up the road afterwards to retrieve the bikes. But I figured out a scheme where biking might still makes sense. I have a foldable bike I’ve been itching to use on a trip, and this seemed like the perfect trip. I would bike up on my mountain bike, do the traverse, then bike back up on my foldable bike. To return I would fold up my foldable bike, strap it to my backpack, and ride out on my mountain bike. This would mean I wouldn’t have to do any road walking. I would be able to save energy and time at the beginning of the traverse, and also increase fun.

Duncan didn’t have a foldable bike, but he did have an electric fat bike. He planned to also bike up at the beginning. Then at the end he would run back up the road and bike back.

Friday night we met up at Newhalem, dropped off my Forester at the Pyramid Lake trailhead, then drove back to Cascade River Road in Duncan’s truck with all the gear in the back. Not unexpectedly we encountered quite a few cars parked on the side of the road near the road closure. It seemed like a low chance of getting any sleep if we squeezed in there, given that we’d be bivying outside and more cars would likely be rolling in all night. So we drove back down to the pullout at milepost 16, a few miles down the road. We were the only ones there. We packed up our gear, laid out sleeping bags, and were asleep around 11pm.

We were up and moving by 1:45am after a few hours nap. Since Duncan had the electric fat bike we decided to just start biking from there. He brought a small length of rope so he could pull me while I rode a normal mountain bike. We couldn’t figure out any obvious and easy attachment system for the rope to my bike that wouldn’t have a high risk of flipping me over. So I ended up just holding the end of the rope in one hand and my handlebars with the other. It actually worked surprisingly well.

We cruised up past the gate at milepost 18, past a few climbers packing up gear. Then we went around the concrete barrier at the park boundary. There were a few blowdowns to negotiate but after about 20 minutes we made it to the Eldorado parking lot. Just before the lot is a significant washout on the side of the road that will likely take a while to repair. A few people were tenting at the lot and looked to be almost ready to head up.

After locking the bikes up in the trees we found an easy crossing on the creek and soon reached the Eldorado climbers trail. There was a lot of fresh debris over the trail lower down, and I lost it for a while, but we eventually found it again and made quick progress. A bit of snow started at the bottom of the boulder field, and we switched into ski boots there. Normally I would stash trail runners in the trees there, but since we were doing the traverse we kept the trail runners in our pack.

Unfortunately the snow soon ended and we had to scramble the boulder field in our ski boots. Finally around 4,500ft the snow became continuous and we put skis on, just as the sun was coming out around 4:30am. It was a bit icy, but ski crampons helped for that. It looked like we were the first ones up that morning, though there were some headlamps below us on the boulder field. We briefly

switched to crampons when the route got a bit steeper, but finished off on skis up to the ridge crossing over to Roush Creek.

There were a few tents on the ridge, but I think the occupants were still asleep. From the ridge I cramponed down the steep and

icy gully on the north into Roush Creek. We then continued skiing up following old skin tracks from Friday. A solo skier was above us also heading up. As we crested the edge of the Eldorado Glacier plateau we finally emerged into the sun and stopped to rope up.

It was actually surprisingly cold up there. A strong wind blew from the southwest and the snow was fresh drifted powder. I’d seen about a foot of snow had fallen there on Thursday, and it was still blowing around. We zipped across the glacier and took a short break at the Eldo bivy sites on the ridge. Duncan took a nap, but I wasn’t tired enough to fall asleep so I just admired the view. A solo skier was just getting up from a bivy nearby. Soon two other skiers caught up to us and a group of four emerged on the glacier. It looked like it might be a crowded day up there. The group of two had trail runners strapped to their pack and I thought they might also be doing the traverse, but turned out they were going for Eldo.

We soon started up again, following a good skin track around Eldorado and traversing along the Inspiration Glacier. We stopped at the Tepeh Towers col just as a group of four skiers was returning to camp from Klawatti. They had attempted the south face route and were planning to head out that day. There were no more tracks across the col on the McAllister glacier and we figured we might be on our own the rest of the day.

We packed up the rope there and continued skiing down the McAllister. I made fun turns down the glacier, through tricky crust, then traversed over to the Eldo-Dorado Needle col. Duncan and I had come here in May 2018 and climbed Dorado Needle, so we didn’t need to make any side trips this time. The goal of this trip was the traverse, not necessarily side peaks. At the col we roped back up and I broke trail on a rising traverse up and around Dorado Needle. We aimed for the obvious col north of the peak at 8,000ft.

Just below the col we stopped for a break and strapped skis to our packs. I then led up in bare boots kicking steps in the steep but slushy slow. The snow changed to ice at the col, but I was able to get decent foot holds on rocks on the sides and made it all the way to the col. There I clipped in to a good rap anchor and pulled the rope up for Duncan. I’ve never had to rappel with skis before, but it’s actually required for this traverse to cross west off the McAllister Glacier.

I backed up the anchor, threaded the rope through, and rapped down. It’s only about a 10m rappel, but is still too steep to easily downclimb in ski boots, so definitely makes sense to rappel. Duncan made it down and we took a short break to put the skis back on. The next section illustrated the true advantage of skis on this trip. It was a very long and fast descending traverse on the southwest side of the Perdition-Coccyx ridge. The snow was firm with a thin layer of corn on top, which made for excellent skiing.

We made quick progress, trying to stay high as much as possible. Just below Perdition Peak we encountered a cliff band that would require a slight ascent to get above or a big descent to get around. We waivered on the best option, but eventually decided to descend. We made fun turns below the cliff band, then tried to keep traversing as high as possible while minimizing elevation loss. Views down the Marble Creek valley to the west were amazing, with lush green foliage down low contrasting with snowy slopes above. We eventually reached a point around 6,000ft just below Lumbar Point and decided to switch back to skins. We were at the edge of trees and nearing the crossing point on the west ridge of the Coccyx.

We skinned up higher and surprisingly came across a fresh set of skin tracks. Upon inspection they looked to be heading southeast towards Dorado Needle. They definitely looked like they were from that day, but somehow we hadn’t seen the skiers and couldn’t see anyone in the distance. Most likely they had crossed above the cliff band just as we were crossing below, and we’d missed each other. It appeared they were doing the traverse in the opposite direction, so that was nice since it meant we’d likely have tracks to follow the rest of the way.

We crossed the southwest ridge of the Coccyx at 6,100ft, then traversed around to gain the north ridge at a small saddle. This was the top of the Ice Elation couloir, and rumored to be one of the funnest lines on the route. We switched into downhill mode and I led the way down the couloir. The snow was a bit mushy from the recent foot of powder softening, but this made for very fun turns. I dropped about 1,500ft all the way to a flat basin at 5,000ft.

At the basin we melted some snow for drinking water, then began skinning steeply up the gully on the north side. It was getting hot in the afternoon sun and we were happy to have made a few liters of water. At the ridgecrest we skiied back down above Wilcox Lakes, then skinned up towards Isolation Peak. Unfortunately the tracks from the other group weren’t really visible anymore. We roughly followed the south ridge, then switched to booting and traversed across a steep wide snow gully and up to the east ridge at 6,700ft.

Here we made a navigation error. The correct route would have been to ski down the east ridge to 6,300ft, then cut north. But we saw a steep but doable north face at 6,700ft. We downclimbed carrying skies until it got less steep, but then were forced to traverse skiers right on another steep slope above a short cliff band. This cost a lot of time slowly downclimbing instead of skiing.

At the base of the cliff we melted some more snow, then continued on skis. We skinned diagonally up to the north ridge of isolation peak, then crossed over to the west side. Here we found ski tracks again, and followed them traversing through a SW facing bowl. The terrain leveled out after that, and we skinned up to the Snowfield-Horseman col by 8:30pm. Our pace had been a bit slower than hoped for with the navigation issues and mushy snow, but it looked like we still had time to get below treeline before sunset.

Clouds were starting to cover the Coccyx and Dorado Needle, as well as Horsemans Pack to the west. Luckily they appeared to be holding off from the Neve Glacier.

The sky turned into a brilliant pink and purple on the peaks of the Pasayten to the

northwest and Colonial Peak to the north. We ripped skins and soon started down.

It was fun magic carpet skiing down the low-angle neve glacier heading into the setting sun in the northwest. The snow was just starting to ice up, but was still soft enough to make fun turns. As we dropped lower we passed into a cloud layer and visibility dropped significantly. We made dollar signs around the other ski tracks, and it helped that I had already climbed this route three times before (two for snowfield and one for Horseman’s pack a few weeks earlier).

We skinned up to the Neve-Colonial col, which was back above the clouds, then skied more fun turns down the Colonial Glacier. By the time we started traversing below Pyramid Peak it was finally dark enough to warrant headlamps. We started skiing across in downhill mode, but then midway realized that wouldn’t get us the whole way across. So we stopped to transition.

As Duncan removed a ski I saw it slowly inch down the slope. I yelled for him to catch it but it was too late. The ski slid down, bounced over a rock band creating sparks, then was gone. It was hard to be sure, but I thought I saw it eventually come to a stop. Duncan downclimbed a ways and eventually came back up with the miscreant ski. That situation could have turned out much worse, and we were lucky to not have lost the ski.

We continued across on skins to the northeast ridge, then stopped to transition again on top of a hill at 5,800ft. There we saw a tent anchored by skis. Maybe they were planning to go for Snowfield or the traverse the next day. I wouldn’t have minded going to sleep then, but we still had a ways left.

We made fun turns down the ridge to about  4,800ft, but then the snow got too steep, icy, and tree-welled to continue. We booted down from there occasionally following tracks but generally following the ridge crest. By 3,600ft the snow ended and we switched back to trail runners. Eventually we picked up the climbers trail and had an easy hike back down to Pyramid Lake. By 1:45am, almost exactly 24 hours after starting, we popped out at highway 20 back to my forester.

I had said I would be home that night, so we quickly threw the gear in and started driving. We drove back up to Duncan’s truck on cascade river road and I dropped off Duncan and picked up extra gear stashed in the truck. Duncan planned to just go to sleep right there, but I drove back up to the gate at the park boundary. There were still a dozen cars parked, but I found a spot right next to the gate.

I opened up my foldable bike, threw on an empty backpack, and started biking back up the road. Biking was much faster than running, and I was happy to have the foldable bike. I soon reached the Eldo trailhead and unlocked my mountain bike. I then folded up the foldable bike, strapped it to my backpack, and biked back out to my forester. By 4:30am I finally made it back to Duncan’s truck at milepost 16. I figured I was too tired to drive home immediately, but might be ok after a short nap.

I set my alarm for 5:30am and soon fell asleep in the drivers seat. After an hour nap I got up and it was already light. I felt much more alert, so started driving. After picking up some skittles and red bull in Marblemount I was able to make it back home in Seattle by 8am.

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