Alaska
Denali’s two high points, the north and south summits, are visible in the upper center of this NASA image. The south summit is the higher of the two, at 20,310 feet.
After being called Mount McKinley for nearly a century, the original Athabaskan name of Denali, meaning “great one,” was officially restored in 2015. And a great one it is. Not only is Denali the highest mountain on the North American continent at 20,310 feet, it’s still growing taller by nearly half an inch a year. From the air, however, Denali can be hard to pick out from surrounding peaks in the Alaska Range. Its double summit is sandwiched between the white expanse of the Kahiltna Glacier to the west and the elongated Tokositna Glacier to the south.
The Denali Fault (a tectonic fault named for the mountain) is part of the greater continental-wide strike-slip fault system that runs along the west coast of North America and includes the notorious San Andreas Fault in California. Strike-slip faults, also called transform faults, occur when two adjacent plates slide past each other, sometimes moving smoothly and other times becoming stuck, eventually releasing their stored energy all at once in the form of earthquakes. This intracontinental fault system is in turn connected to—and driven by—the offshore subduction zone where the Pacific Plate is diving under the North American Plate at a rate of about an inch per year.
Over time, movement along the Denali Fault has given rise to the Alaska Range and Denali. Continued movement along the Denali Fault, which runs under the Alaska Range, accounts for Denali’s ongoing ascension. The north face of Denali, known as the Wickersham Wall, is the largest vertical mountain face on Earth—higher than any face on Mount Everest. From the base of the Wickersham Wall, at 5350 feet of elevation on the Peters Glacier, to the north summit, the face soars upward for nearly 14,000 steep, vertical feet. The avalanche-swept direct route up the face is so dangerous it has only been climbed once, in 1963, by a team of alpinists from the Harvard Mountaineering Club.
Denali continues to gain height because of action along the Denali Fault. The north face, known as the Wickersham Wall, is the planet’s largest vertical mountain face.
The distinction between the highest mountain and the tallest mountain is an important one in geology, and in mountaineering. The highest point on Earth is the summit of Mount Everest, at 29,029 feet, as measured from sea level. But the tallest mountain is measured from base to summit. By this metric, Denali is taller than Mount Everest, as it rises more than 18,000 feet from its base, while Everest stands only 12,000 feet above its base, which sits on the already high-altitude Himalayan Plateau. Both Everest and Denali are dwarfed by the Mauna Kea volcano on the Big Island of Hawaii, which, measured from its base on the ocean floor to the summit, is 33,476 feet tall. However, its elevation above sea level is a mere 13,808 feet.
Denali may be visible en route to Fairbanks, Alaska, which lies a hundred miles to the north of Anchorage.
