Hubbard Glacier

Hubbard Glacier is a tidewater valley glacier that straddles the Alaska-Canada border, reaching the sea within Wrangell-St. Elias National Park and Preserve in Alaska after flowing from sources in Kluane National Park and Reserve in Yukon, known to the local Tlingit as Sít' Tlein. The glacier runs about 76 miles from its source to its tidewater face, and ice takes roughly 400 years to travel that length, with the glacier regularly calving icebergs as large as ten-story buildings. Unlike most glaciers worldwide, Hubbard has been advancing for about a century, and in 1986 it surged forward far enough to seal off Russell Fjord, creating a temporary lake whose water level rose 82 feet before the ice dam failed that October, releasing an estimated 5.3 cubic kilometers of water in what is recorded as the largest glacial lake outburst flood on record. A magnitude 7.0 earthquake near the glacier in December 2025 raised concerns about further landslide activity in the area.