Idaho is a mountainous state with an area larger than that of all of New England. Idaho's mountains, lakes, streams, and extensive wilderness areas make it a haven for outdoor activities.
Principal ski areas include Silver Mountain, near Kellogg; Schweitzer Basin, near Sandpoint; Brundage Mountain, near McCall; and Bogus Basin, near Boise. The world-famous Sun Valley, opened in 1936 by the Union Pacific Railroad, is an important summer and winter resort.
Hunters travel from around the world to search for big game in the state's backcountry, some of which is accessible only by foot or horseback.
Idaho is also renowned for sport fishing, especially in the northern rivers and lakes, where there are several varieties of salmon and trout.
Craters of the Moon National Monument covers 84 sq. miles of extinct volcanoes and lava formations in the south central part of Idaho. In City of Rocks National Reserve, in southern Idaho, are odd granite clusters that resemble villages. Nez Percé National Historical Park, which includes a portion in northern Idaho, is dedicated to the history of the Nez Percé people and the Lewis and Clark Expedition.
A small section of Yellowstone National Park extends into northeastern Idaho at the Wyoming state line. The Hagerman Fossil Beds National Monument is on the Snake River, the carving action of which has exposed extraordinary fossil beds.
The ten national forests in Idaho cover 20.4 million acres, or about two-fifths of the state. Idaho's national forests are noted for their magnificent scenery, variety of wildlife, and superb stands of tall timber. They also include large areas of grassland and rocky mountain slopes. Boise National Forest, in western Idaho, is the largest and covers more than 2.6 million acres.
Most of the forest lies within the Idaho Batholith a large and highly erosive geologic formation. Through uplift, faulting, and subsequent dissection by streams, a mountainous landscape has developed. A portion of the Frank Church-River of No Return Wilderness, the Sawtooth Wilderness, Sawtooth National Recreation Area, and the Middle Fork of the Salmon River, a part of the National Wild and Scenic Rivers System, are near or in the forest.
The Challis National Forest has a diversity of landscapes, including the rugged exposed heights of Borah Peak, Idaho's tallest mountain. Stretching between Oregon and Montana in north central Idaho is the Nez Percé National Forest.
Within it is the canyon of the Snake River, the deepest gorge in North America. At Hells Canyon, on the Idaho-Oregon state border, there is a vertical drop of about 7000 feet.
More than 2.5 million acres of the Idaho Panhandle National Forests, which extends into eastern Washington and western Montana, lie within northern Idaho. The forest includes some of Idaho's most scenic mountain ranges the Selkirk, Cabinet, Coeur d'Alene, and Bitterroot mountains and three of Idaho's largest lakes (Pend Oreille, Coeur d'Alene, and Priest lakes). The state's other national forests include the Caribou, Clearwater, Payette, Salmon, Sawtooth, and Targhee.