Idaho County is a rural county in the U.S. state of Idaho. It had a population of about 16,267 at the 2010 census. The county seat and largest town is Grangeville. Much of the county is mountainous and forested; a distinctive feature is that the county is divided by the Salmon River and straddles two time zones: most of the area lies in the Pacific Time Zone while areas south of the Salmon River observe the Mountain Time Zone.

Geography and environment

Idaho County is the largest county by land area in the state and contains a mix of deep river canyons, high plateau, and forested mountain ranges. Major waterways include the Salmon and Clearwater river systems. Large tracts of federal forest and wilderness lie within its borders, including portions of national forests and remote wilderness areas that support diverse wildlife and recreation opportunities.

History and people

The area has long been inhabited by Indigenous peoples, notably the Nez Perce, and later drew settlers during the 19th-century territorial era. Settlement patterns have remained sparse; towns grew around timber, ranching and small-scale mining. Demographically the county is rural with a small, dispersed population concentrated in a few communities such as Grangeville, Cottonwood and Riggins.

Economy and land use

Economic activity in the county has traditionally centered on natural resources: timber, livestock grazing and limited mining. In recent decades recreation and tourism—driven by hunting, fishing, rafting and hiking—have become increasingly important. Local services, small-scale agriculture and public-sector employment also support the region.

Recreation, conservation and access

  • Outdoor recreation: whitewater on the Salmon River, backcountry hiking, fishing, and big-game hunting.
  • Conservation: significant portions of national forest and designated wilderness protect habitat and scenic landscapes.
  • Access: long distances between communities and limited road networks make the county remote in places; river corridors and forest roads are important travel routes.

Notable facts include the county's time-zone split along the Salmon River and its role as a gateway to some of Idaho's most rugged public lands. Visitors and residents alike rely on the natural environment for livelihood and recreation, and ongoing land-management decisions balance resource use with conservation and access. For further local details see county resources and regional guides.