The
Alaska Peninsula is a
peninsula extending about 800 km (500 miles) to the southwest from the mainland of
Alaska and ending in the
Aleutian Islands. The peninsula separates the
Pacific Ocean from
Bristol Bay, an arm of the
Bering Sea.
The Aleutians are a highly active volcanic mountain range which runs along its entire length. It contains several U.S. National Parks and Wildlife Refuges, including the Katmai National Park and Preserve, the Aniakchak National Monument and Preserve and the Becharof National Wildlife Refuge, the Alaska Peninsula National Wildlife Refuge, and Izembek National Wildlife Refuge.
The southern-most side of the Alaska Peninsula is rugged and mountainous, created by the uplifting tectonic activity of the North Pacific Plate subsiding under a western section of the North American Plate; whereas the northern side is generally flat and marshy, a result of millennia of erosion and general seismic stability.
The differences between the northern and southern shores of the Alaska Peninsula are a study in contrasts. While the northern Bristol Bay coastal side is generally turbid and muddy, experiences tidal extremes, and is relatively shallow, the Pacific side has relatively small tidal activity and is very deep and clear.
