Mt. Aetna
Grand Couloir
 Difficult Class 2 
Snow Steepness: Moderate  
Trailhead:Boss Lake
Start:9,700 feet
Summit:13,745 feet
Total Gain:4,100 feet
RT Length:7.50
Weather:NOAA Forecast
Conditions:26 reports
Cell Signal:1 report
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? (WINTER) HOLD ON! If you don't have much high-elevation, winter climbing experience, be careful in your planning and take a partner. All 14er routes are more difficult and more dangerous in winter.


From the intersection of U.S. 285 and U.S.50, just north of Poncha Springs, take U.S. 50 west for approx. 12 miles. Just after the Monarch Lodge, turn right into the parking area for Monarch Snowmobile Tours. Pass their building to find the start of Forest Service Road 230 and a small parking area just beyond the start of 230.


You may have seen it - here's a view of Aetna's Grand Couloir, from Monarch Pass - 1. This classic line should only be done as a snow climb and is skied by many people each Spring. Park in the small, Boss Lake trailhead parking area or across the highway at Monarch lodge and start your day by walking up Forest Service (FS) road 230 - 2 and 3. Pass the turn-off for Boss Lake after 1.5 miles ( 4) and continue another mile to reach a corner, where the view opens up to the southwest - 5. Walk around the corner and turn right to enter the large run-out below the Grand Couloir - 6. If you've previously only viewed the Grand Couloir from Monarch Pass, you might be surprised by how low-angle it looks from this vantage but don't be fooled, this foreshortened view cannot hide the fact that there's 2,900' of gain between you and the summit.

Continue northeast across the openness of the run-out and begin your ascent of the Grand - 7 and 8. Pass through a narrow-ish section between 11,600' and 11,800' to reach easier ground, near a slight turn in the couloir - 9. Once above 12,000', the remaining 1,800' to the summit becomes obvious - 10. Continue climbing north - 11, 12, 13, 14 and 15. Between 13,100' and 13,400', the couloir steepens to approx. 38 degrees and is the crux of the route. Above 13,500', angle northeast ( 16 and 17) to gain the summit ridge and the top of Mt. Aetna - 18 and 19.


#1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15 #16 #17 #18 #19

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