Lake Clark National Park and Preserve is a composite of ecosystems representative of many diverse regions throughout Alaska. Within the park the mountains of the Alaska and the Aleutian Ranges join, creating the Chigmit Mountains, an awesome, jagged array of peaks resulting from centuries of uplifting, intrusion, earthquakes, vulcanism, and glacial action. Two active volcanoes, Iliamna and Redoubt, vent steam from their snow-capped peaks, rising more than 3,050 meters (10,000 ft.) The Chigmit's eastern flank descends rapidly to Cook Inlet. Rivers cascade dramatically to the sea through forests of Sitka and white spruce. The rocky cliffs in and adjacent to the park provide rookeries for puffins, cormorants, kittiwakes, and other seabirds. The western flank of the Chigmit Mountains descends through tundra-covered foothills to boreal forest. Spectacular lakes and wild rivers fill the valleys, flowing southwestward to Bristol Bay.
Summer is the time of life as caribou calve, buds turn to leaves, mosquitoes hatch, and salmon return to spawn. Fireweed, lupine, blueberry, and bearberry abound. In autumn the burgundy-hued tundra blankets the slopes around Turquoise Lake. Fish include five species of salmon, rainbow trout, Dolly Varden, lake trout, northern pike, and arctic grayling. Dall sheep, caribou and moose forage the area. Brown and black bear are present, as well as wolves, lynx, foxes and other mammals.