Mt. Eolus

Route: Chicago Basin Approach
Posted On: 6/12/2025, By: Jgeeez
Info: Typing this as the train nears Durango. All of the fallen trees are cleared up through Chicago Basin. Still a good amount of snow 12,500’ and up, twin lakes is mostly frozen. The summit ridges of Eolus/N Eolus are clear of snow. All of the Eolus group require snow field climbing right now, and it’s post-holing season! Sunlight had the most snow to climb and it softened real quick in the day. Micro spikes and an ice axe sufficed! 

Route: Chicago Basin Approach
Posted On: 6/2/2025, By: dakotasmama
Info: There are 91 trees across the six miles of trail into Chicago Basin that are large enough you have to climb over, shimmy under, or route find around (at least 91 - every time I wasn’t sure which number I was on, I went with the lower of the two). So keep that in mind when planning how long it will take. I packed in snowshoes for the section above Twin Lakes and they only helped a little - dangerous, deep, soft spring snow conditions all the way up to the notch - I fell and slid backwards approximately 500 feet on the way up, then the snow collapsed under one leg on the way down and it took over 15 minutes to free it. There’s a huge crack about halfway down the couloir and I was terrified it would avalanche the entire time. Once I got to the notch I did Eolus first, lots of mud and running water so I was very careful, especially across the catwalk. After all of that, North Eolus was the quickest, easiest scramble ever. Took nearly 9 hours to go from Chicago Basin to the summits and back. 

Route: Chicago Basin Approach
Posted On: 5/15/2025, By: AlpineSplit
Info: After getting off the train at Needleton, we were able to walk all the way to camp at 11K in runners. There is almost no snow until you get into twin lakes basin at 12K. Once you are on the bench at twin lakes there is plenty of snow and we skinned up to the base of the east couloir and booted up and onto the west side to the summit. West side has continuous snow from the summit, but the summit will only be in for another few days. Good conditions down the east couloir at 8am. 

Route: Chicago Basin Approach
Posted On: 10/11/2024, By: La Mosca
Info: Finished up my 58 on N. Eolus and Mt. Eolus yesterday. The whole basin is basically dry. Based on what I could see, there may be a tiny bit of snow still on the Windom route. Time running out to catch the train, but if you can, the conditions in there are great, and fall colors are still near-peak on the way up. Cheers! 

Route: Northeast Ridge
Posted On: 9/9/2024, By: Joey_parm
Info: I would consider bringing microspikes for all peaks in the basin now. Fairly moderate graupel storms occurring overnight resulting in some slippery conditions all the way up if exercising an alpine start. I was glad to have mine, as the sun was still rising when I made it to the saddle. Most others appeared to start much later to allow for melt, but at that point you would likely be contending with potential afternoon weather at noon while still up high. Even then, spikes would still help on melting ice and wet rock - especially on the way down. 

Route: Chicago Basin Approach
Posted On: 9/3/2024, By: Abowser7
Info: Beautiful conditions on all 4 peaks. Hiked in on Saturday from Needleton to Chicago Basin and started the hike to the peaks on Sunday at 4:30am. Summited Eolus at 7:45, North Eolus at 8:15, Sunlight at 11:30, Windom at 12:30. Got back down to our campsite at 2:00 just in time for the worst hailstorm from 4-7:30pm. It seemed to melt out quick as we hiked back to Needleton the next morning. Still summer conditions with zero snow crossings. Get it while you can! Been wanting to do these peaks for over a year, but the logistics of all of this always turned me away. Booking tickets is very easy and the train is about 2.5 hours to Needleton from Durango (8:15 departure time). The train picks you up on its way back from Silverton around 2:45-3:00pm. You can expect to be back in Durango just after 5:00pm. Beautiful hike, well worth it. 

Route: Chicago Basin Approach
Posted On: 7/31/2024, By: Istoodupthere
Info: Climbed Eolus and N Eolus from Purgatory. My garmin said 39.7 miles and 10,108 of gain. One of my favorite climbs. The hike in and out? Ill take the train next time. A guy who did the route the day before me saw a mountain lion just off trail by where there is an old carcass on the trail, 2 miles or so from trailhead. What I assume was a bear closer to the bridge before the needleton turn off made a few close crashing steps towards me in some thick brush. Got my adrenaline going. For me the crux of the route was the last 4.5 miles back to the trailhead where there was about 2400 feet of gain. 85 degrees when back at trailhead. I was exhausted. Campsites start about 4.75 miles from bridge at needleton turn off. I got to that area around 3:30pm and had to do some searching for a campsite. Probably 50 people in the basin. Close to 20 of us summiting around same time. Maybe the most solid grippiest rock Ive been on in CO. Lightweight gloves not a bad idea so your hands dont get cut up. Twin Lakes Basin is a special place. Mosquitoes only bad for me around dusk. Flies were bad around camp. 

Route: Chicago Basin Approach
Posted On: 7/15/2024, By: caesarsalad
Info: No snow on the trail (some right next to it though). A few sections of wet rock, but not on any of the class 3 stuff. 

Route: Chicago Basin Approach
Posted On: 7/1/2024, By: tlinkus
Info: Snow covering part of the lower trail before the ramp. Easy to bypass by walking through rocks near the trail. Small 10ft section of snow to get on the ramp itself. Can avoid snow on ramp, but rock is wet and slick. Several small snowfields to cross on way up to saddle, rock in between is slick. No snow on catwalk. Minimal snow on upper section that can be avoided. Did watch a large rock come off near the peak about 200ft from us and tumble down the entire mountain. No gear needed, careful with wet and loose rock. 

Route: Northeast Ridge
Posted On: 10/18/2023, By: SnowmassCD
Info: I did the regular routes on the 4 Chicago Basin 14ers this morning. Mostly summer-like conditions persist except for on Windom. Eolus: Small snow patches, but avoidable. No traction required. Some of the ledges also have slick mud from recently melted snow. N Eolus: Dry on the class 3. Some small snow patches about. Sunlight: Mostly dry on the route, some small snow patches. Windom (traverse from Sunlight): Like being on another planet versus the summer-like condition of other mountains. 1-2 of mostly unconsolidated - but sometimes bulletproof - snow getting to the ridge from Sunlight. Snow on the shady side of the ridge the whole way up. I used gaiters and an axe. Traction might have been nice on the consolidated snow, but I didnt use any as it was mostly super unconsolidated. Gusty winds up top created major spindrift falling down the gullies you cross on the traverse. 

Route: Northeast Ridge
Posted On: 9/25/2023, By: JasonCrane
Info: Did the Durango-Silverton Train to Chicago Basin for the weekend backpacking adventure. Mt. Eolus is holding a bunch of snow on the north/northeast face (backside,) but it's 99.9% dry along the zig-zagging cairns & ledges. Most climbers should have no issues at all on the catwalk & it's plenty wide for the most part not to succumb to exposure. If you stay towards the center between the northeast ridge & deep, snow-filled colouir, you can just follow the cairns up to the summit by zig-zagging ledges. If you find yourself trying to ascend a Class 4 chimney or in an uncomfortable spot, you're off trail & need the re-trace back towards the middle & pick-up the cairns. North Eolus is a straight line from the notch/saddle, but does require some scrambling on dry rock. No need for spikes or an axe. Ran into Will_E coming down at the end of legendary Eolus Grand Slam all the way in & out of Purgatory!!! Epic! 

Route: Northeast Ridge
Posted On: 9/24/2023, By: andlours
Info: Summer conditions. Ledges were a little muddy from the recent snow melt. 

Route: Overlook
Posted On: 9/20/2023, By: Jorts
Info: I ran up to the overlook to put eyes into Chicago Basin. Things are looking dry. Vantage point is from the SW though so this could be deceptive. 

Route: Northeast Ridge
Posted On: 9/3/2023, By: Briere
Info: Full summer conditions still; free of snow! Tricky route finding on the final wall since there is so many cairns up there. 

Route: Northeast Ridge
Posted On: 8/19/2023, By: Snommed1
Info: Mt Eolus/N Eolus...99% summer conditions. One small snowfield to cross (~30yd, see picture) with an easy go-around if snow is still frozen over. Mosquitoes have abated in Chicago Basin. None to speak of. Not a lot of Needle Creek water access points up to Chicago Basin if you had planned to filter water along the way. Wear sunscreen.