The longest valley glacier in North America hides in the remote Alaskan wilderness.

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: Stretching 53 miles through the Wrangell Mountains, the Nabesna Glacier holds the title of the longest valley glacier on the continent. Fed by forty tributary glaciers, this massive river of ice flows from a volcanic icefield, serving as a vital, icy gateway for mountaineers and researchers exploring the eastern Alaskan range.

Originating from the northern slopes of the 14,163-foot Mount Wrangell, a massive shield volcano, the Nabesna Glacier is a defining feature of the Alaskan landscape. It carves a path past significant peaks such as Mount Blackburn and Atna Peaks before turning north. Its terminus sits at an elevation of approximately 3,000 feet, where the melting ice gives rise to the Nabesna River, which eventually feeds into the Tanana River.

The glacier serves as a primary access point for those venturing into the heart of the eastern Wrangell Mountains. Ski mountaineers, climbers, and scientists rely on the glacier for passage. During winter months, when snow blankets the ice and crevasses, ski-equipped bush planes can land on the central portion of the glacier at elevations between 6,000 and 7,000 feet. The glacier was officially named in 1902 by F. C. Schrader, a member of the U.S. Geological Survey.

While the Nabesna is currently the longest interior valley glacier in the world, it has been shrinking steadily for over a century. Observations suggest this recession has been occurring since the start of the 1900s, though geological evidence implies the glacier was once significantly larger. Deposits found far down the valley indicate that at one point in its history, the glacier may have extended for more than 200 miles, highlighting the dramatic environmental shifts that have shaped this region over time.

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