With a summit elevation of 20,320 feet above sea level and a greater base-to-peak height than Mount Everest, Mount Denali is considered one of the most difficult climbs in the world. On June 7, 1913, four climbers reached the south summit of Denali (better known, at the time, as Mount McKinley), the highest peak in North America. It was the first successful ascent to the pinnacle. A handmade American flag was raised on the Alaskan summit that day, stitched together during the ascent using materials from the climbers’ gear.

The team that summited Denali included Hudson Stuck, Harry Karstens, Walter Harper, and Robert Tatum. Hudson Stuck, then Episcopal Archdeacon of the Yukon, had followed the exploits of mountaineers who made forays on Denali, and he decided to make his own essay of the imposing massif. Stuck had climbed in the Alps and Rockies, and as a missionary to the native peoples of Alaska had traveled widely by dog sled. Harry Karstens (later the first superintendent of Mount McKinley National Park) had been a Klondiker during the Alaska gold rush and gained fame as a fearless long-distance dog-musher. Walter Harper was a young man of mixed Scottish and Athabascan descent who accompanied Stuck on his many travels.

The 21 year-old Tatum, a postulant for holy orders and Tennessee native, was teaching at the Episcopal mission school at Nenana, Alaska when he met Stuck on one of the Archdeacon’s regular visits to the mission. Stuck enlisted Tatum as the camp cook for a planned ascent of Denali the next year. Even a trek to base camp would be a mountaineering feat. Tatum, the only inexperienced climber in the party, trained by hiking more than a thousand miles during the winter months that preceded the expedition. It was mere happenstance that Tatum joined the climb to the top. Just one week before the scheduled departure, Stuck invited Tatum to replace another climber who was unable to join the team.

The team set out from Nenana in mid-April. Assisted by two Athabascan boys, the adventurers relayed supplies over 100 miles by dog sled before beginning their climb. Over twelve weeks, they braved bitter cold, altitude sickness, treacherous crevasses, and the constant threat of avalanches to reach the summit. To an ordinary mortal, it would seem an almost unimaginable ordeal.

Read more about the ascent of Denali as recorded in Robert Tatum’s diary. Photographs taken by Tatum may be viewed here.