In the U.S. state of Idaho, U.S. Route 95 (US-95) is a north–south highway near the western border of the state, stretching from Oregon to British Columbia for over 538 miles (866 km); it was earlier known in the state as the North and South Highway.

The Boise, Idaho Metropolitan Statistical Area (MSA) is an area that encompasses Ada, Boise, Canyon, Gem, and Owyhee counties in southwestern Idaho, anchored by the cities of Boise and Nampa. It is the main component of the wider Boise–Mountain Home–Ontario, ID–OR Combined Statistical Area, which adds Elmore and Payette counties in Idaho and Malheur County, Oregon. It is the state's largest officially designated metropolitan area and includes Idaho's three largest cities: Boise, Nampa, and Meridian. Nearly 40 percent of Idaho's total population lives in the area.