The Gulf of Alaska is an arm of the Pacific Ocean defined by the curve of the southern coast of Alaska, stretching from the Alaska Peninsula and Kodiak Island in the west to the Alexander Archipelago in the east, where Glacier Bay and the Inside Passage are found.

The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east.