Westman is dead on with the route description. We planned for 3-4 days on route, took food accordingly and fuel for 6 days. Firstlight makes a pretty sweet bivy shelter these days. We still carried 0˚ bags, foam pads, etc. Trick is to bring only what you will definitely use. Definitely worth the effort!
According the the USGS maps, as well as my altimeter when we climbed it, the elevation at the bergschrund of the Japanese Couloir is about 12,400'. Kahiltna Notch is indeed lower, but that glacier shelf at the foot of the route gets you higher than the notch before the real climbing begins. True that if you start on the east fork like the Italians (pretty sure this hasn't been done in decades) then you start climbing at 11,500'.
The grade is (as always) debatable, owing to the "alpine" factor. In rock shoes in the valley, it's probably 5.4. The 5.8 grade is "feels like" when adding in boots and a pack. My take is, it's 5.4, the variables added don't change what it actually is. :)
A 10+ day ascent was normal in the early 70's and 80's, but by modern standards that would be an unthinkably long time to be on it. Pre-acclimatizing on the west buttress is standard these days, then blasting the route in 2-4 days when the weather gets settled. I consider proper "acclimatization" to mean going all the way to the summit of Denali if possible prior to making the attempt on one of the harder routes. If this is done, altitude should be no factor, it's extra fitness, and then you can cruise it. In the past three years, there have been three one day (14-16 hour!) ascents, in addition to Mugs' 15 hour ascent in 1991. Even people taking bivi gear in the past 10 years rarely take longer than 4 days, and most take 3.
Given that high pressure systems in the range rarely last longer than 4 days, if you plan for a seven day ascent, you're almost surely guaranteed to have the nice weather you started up in dissolve on you somewhere above 16,000', at which point bail out options have become grim.
All that said, big respect for doing the route, particularly for when you did it (81). It was way badass then, and while standards and tactics have changed, the route itself hasn't: it is still badass!
A number of points: 1. relief (length) -- 8000' measures from the "Kahiltna Notch" (12000') to Denali's summit, but the Cassin Ridge route begins 2000'lower where the Japanese Couloir leaves the NE Fork of the Kahiltna. If you climb the original Italian start, it begins even lower. So you actually have a minimum of 10,000' to climb. 2. the supertopo grading seems overstated. when I did the route in 1981, the most difficult rock climbing seemed more like 5.6 than 5.8. 3. time - may be accurate, but we took eleven days, and passed two parties on the route, only one of which completed the climb, two days behind us. Our original plan had been to allow ten days: five for climbing, and five for rest/acclimatization/storms. We spent an eleventh day because the weather and mountain conditions were so incredibly stellar that we chose to blow an extra day sunbathing and playing cribbage at 19,000'! Briefly, I would not plan for a shorter climb than supertopo's longest estimation (seven days) unless you take time to go high on the West Buttress to acclimatize beforehand. Earlier in the season in which we climbed it, we were told by the climbing rangers that John Roskelley had had to retreat from this route when he developed cerebral edema!
I would caution the reader that this beta is OLD -- I climbed the route with my girlfriend in 1981.
An overview of the mountain.
Photo: Mike Gauthier
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