Hubbard Glacier is one of Alaska's most dramatic icefields. This towering wall of ice at the water’s edge began its long journey about 400 years ago, in the early 1600s. As it flows to the sea, Hubbard is met by Valerie Glacier. The combined surge pushes a wall of ice toward Bert Point, which threatens to close off Russell Fjord from the bay. The closure has happened before—in 1986 and 2002—transforming the fjord into “Russell Lake.” Each time, runoff and rainwater filled the lake, building up an enormous pressure and breaking through the ice wall with a thundering force.