The Southwest Alaska Network consists of five Alaskan park units: Alagnak Wild River, Aniakchak National Monument and Preserve, Katmai National Park and Preserve, Kenai Fjords National Park, and Lake Clark National Park and Preserve. Collectively these units comprise approximately 9.4 million acres, 11.6 percent of the land managed by the National Park Service, and 2 percent of the Alaska landmass. The parks include a diversity of geologic features, ecosystems, fish, wildlife, and climatic conditions that are equal to few places in North America. This network of relatively untouched wilderness parks offers unparalleled opportunities to study ecological systems minimally affected by people.
Southwest Alaska is one of the most geologically active regions on the continent. The Valley of Ten Thousand Smokes in Katmai National Park and Preserve, and Aniakchak Caldera in Aniakchak National Monument and Preserve are two of the many volcanic features of the region. Superimposed on these features are ice and permanent snowfields that blanket approximately one-fifth of the land area of southwest Alaska parks. Valley and tidewater glaciers radiate from massive snowfields along the coastal mountains of Kenai Fjords National Park, Lake Clark National Park and Preserve, and Katmai National Park and Preserve, while rapidly retreating glaciers leave huge deposits of till in their wake. Together, the Southwest Alaska parks span three climatic zones and 11 ecoregions, encompassing an area where Aleutian, low-Arctic, interior-boreal, and Pacific coastal flora and fauna converge.