We make four camps as we climb alpine style, moving all camps higher as we go and leaving none established above or below. It is not uncommon for temperatures high on the mountain to fall as low as -34°C/-30°F , but at lower elevations daytime temperatures on the glacier can reach as high as 21°C/70°F, so we sometimes sleep in the day and ferry loads at night when temperatures are between -9 to -18°C and 0°F to 15°F . The night's cold improves conditions under-foot, and we still have adequate light because of the extreme northern latitude. Double carries are done during the first part of the expedition to ease the work and to help with acclimatisation.
All expeditions begin with a meeting and orientation in Anchorage. We spend one night there, then travel by van the next morning to the small town of Talkeetna. There we repack our equipment, meet our ski plane pilots, and as soon as possible, make the beautiful flight to the Kahiltna Glacier at 2,225m/7,300ft. Soon after our arrival and a review of glacier travel procedures, we begin moving to our first camp.
We establish our Camp 1 at 2,375m/7,800ft at the confluence of the main Kahiltna Glacier and its rugged Northeast Fork, the approach for West Rib and Cassin Expeditions. Enjoying spectacular views the whole way, we continue on to Cache 1 at 2,987m/9,800ft and Camp 2 at 3,413m/11,200ft while snowshoeing up moderate terrain. As we do throughout the climb, we travel in rope teams because of the ever-present crevasse hazard. To ease the burden of moving our expedition supplies, we use specially designed sleds that we tether to our packs and pull along the gentle sections of the lower mountain.
Above Camp 2, the climbing steepens as our route takes us past the terminal walls of the West Buttress. We usually cache our snowshoes at 3,413m/11,200ft and continue our climb with crampons because of the gradient of the route and the hardening snowpack. We climb out of a basin to reach Windy Corner at 3,992m/13,100ft, then make an ascending traverse through seracs and heavily crevassed terrain as we approach the head of the Kahiltna Glacier at 4,328m/14,200ft. We enjoy spectacular views as we look down to the lower Kahiltna and out to 5,182m/17,004ft Mt Foraker. In the other direction the impressive summit bulk of Denali rises above us, and we can easily see the details of the upper West Rib and Messner Couloir, as well as the steep headwall of the West Buttress that we will soon climb. At Camp 3 (4,328m/14,200ft), we take a well-deserved rest day and make final preparations for our summit bid, reorganizing our gear for the carry to the highest camps.
At this point we move into the most demanding part of the expedition: higher elevations combined with steeper ground. From Camp 3, we ascend 335m/1100ft up a gentle snow slope to the bergschrund at the base of the West Buttress. The bergschrund is at times quite steep but it is short and, with steps established in the ice, not difficult to surmount. We then begin our ascent to the top of the West Buttress on the 275m/900ft headwall of 45 and 50-degree slopes. Typically the pitches are of hard ice with some snow overlaid, and we protect them by using self-belays with jumars on a fixed rope. Because of the steepness of the route and the amount of elevation gained, we may make a double carry to establish Cache 3 at over 4,876m/16,000ft.
Emerging from the headwall onto the top of the Buttress, the atmosphere of the climb changes dramatically. While the earlier parts of the climb have all been on large glaciers and open slopes dominated by immense mountain masses towering above, we now move on an open ridge and enjoy that unmistakable feeling of climbing above most of the surrounding world. As we begin to move along the crest of the Buttress, we gain views across the Peters Glacier to the Alaskan tundra stretching out far beyond, and to the south we can look over the top of Mt. Hunter to the scores of other peaks in the Alaska Range. Initially the ridge is fairly broad, but as we reach the 4,998m/16,400ft level it narrows with steep drop-offs to both the north and south.
The traverse to our final camp, Camp 4 (High Camp) at 5,242m/17,200ft, is one of the most beautiful climbs on Denali. We follow a steadily narrowing crest and at times move between and around a series of magnificent, pointed granite gendarmes up to fifty feet high. The climbing is never steeper than 35 degrees, but the exposure is very significant and requires caution as we move up a route that in some sections is reduced to ledges six feet wide. Further east the ridge finally begins to merge with the main part of the Denali massif, and there we establish camp in a basin just below Denali Pass, the low point between Denali's higher south summit and lower, 5,934m/19,470ft north peak. From this point we will climb to the summit in a single day.
On summit day we make an ascending traverse to Denali Pass, crossing above some very large crevasses and traversing a fairly steep section between 5,364m/17,600ft and 5,486m/18,000ft. From there we climb gentle slopes to a plateau at 5,913m/19,400ft, from which we get impressive views down onto the Harper and Muldrow Glaciers and across to Denali's North Peak. Our final approach to the summit takes us up moderately steep slopes to the crest of the ridge between Kahiltna Horn (6,132m/20,120ft) and the main summit. At the crest we peer down the 8000-foot drop of the precipitous South Face, looking between the Cassin Ridge to our right and the South Buttress to our left. We ascend the summit ridge on its exposed south side for two rope lengths, then cross to the north side for the final pitches that bring us to the 6,193m/20,320ft summit of North America. With steady drops on three sides and the abrupt face to the south, the final steps to the clearly defined summit point are a very exciting finish to a beautiful route.