The park covers an area of 669,984 acres (1,046.9 sq mi; 2,711.3 km2)[1] on the Kenai Peninsula in south-central Alaska, west of the town of Seward.

Kenai Fjords National Monument was initially designated by President Jimmy Carter on December 1, 1978, using the Antiquities Act, pending final legislation to resolve the allotment of public lands in Alaska.

The park protects the icefield, a narrow fringe of forested land between the mountains and the sea, and the deeply indented coastline.

The park is inhabited by a variety of terrestrial and marine mammals, including brown and black bears, moose, sea otters, harbor seals, humpback and killer whales.

[9] Archeological surveys have altered the early view that the area was subject to only transient occupation as evidence has accumulated of long-term use.

It is believed that coastal subsidence and rising water levels have inundated many sites, as the shoreline was the place richest in resources for early peoples.

The survey also found evidence that an earthquake dating to about 1170 AD lowered the shoreline by at least 1.8 metres (5.9 ft), potentially inundating earlier sites.

[13] Follow-up action by Hartzog brought the Park Service into discussions over the Alaska Native Claims Settlement Act (ANCSA).

In 1973 the Nixon administration proposed the Harding Icefield–Kenai Fjords National Monument as part of the ANILCA legislation.

Secretary of the Interior Cecil D. Andrus proposed a 410,000-acre (640.6 sq mi; 1,659.2 km2) Kenai Fjords National Park.

[20] On December 2, 1980, the ANILCA bill was signed into law by Jimmy Carter, converting Kenai Fjords to a national park.

[22] In 1982, a general management plan for the park was finalized, designating Exit Glacier as "front-country," the fjords as "back-country," and the icefield as wilderness.

[23] The park was initially administered by a small cadre of permanent and seasonal rangers and technicians who put considerable emphasis on community liaison.

The tours provide views of land and marine wildlife, particularly Steller sea lions, puffins, Dall's porpoises, American black bear, snowshoe hares, mountain goats, and humpback and orca whales, as well as natural sights such as the fjords and tidewater glaciers.

The process has lowered the elevation of the Kenai Mountains, gradually pulling glacial features down into the sea, which is at the same time rising.

According to the United States Department of Agriculture, the Plant Hardiness zone at Exit Glacier Visitor Center at 463 ft (141 m) elevation is 4b with an average annual extreme minimum temperature of -20.3 °F (-29.1 °C).

The park's glaciers have retreated through the twentieth century, exposing new lands to colonization by plant and animal life.

[60] Birds that nest in this park include bald eagle,[61] the Peale's subspecies of peregrine falcon,[62] black-billed magpie,[63] and Steller's jay.

[64] Marine birds include tufted and horned puffin,[65] common and thick-billed murre,[66] and marbled murrelets.

The alpine regions support shrubby grown to alders, devil's club, elderberry, lady fern, cow parsnip and other plants.

Higher alpine regions support a dwarf shrub community less than 1 foot (30 cm) high, at a very slow rate of growth.

Dwarf plants in this region include bog blueberry, partridgefoot, black crowberry and Aleutian mountainheath, all of which are vulnerable to damage from foot traffic.

[65][68] Kenai Fjords features an unusual estuary formed from the mix of glacial fresh water and seawater.

[35] The grounding of the oil tanker Exxon Valdez in Prince William Sound on March 24, 1989, produced extensive contamination of the Kenai Fjords coastline.

That year Exxon settled with the federal and Alaskan governments, paying about $870 million into a restoration fund, some of which was earmarked for Kenai Fjords.

The site showed that contrary to earlier beliefs, portions of the park had been used over a long term by native peoples.