Boise, Idaho

According to ehuacom, Boise (pronounced: bɔɪsi) is the capital and largest city of the U.S. state of Idaho. The city has 237,000 inhabitants and an agglomeration of 795,000 inhabitants (2021).


According to mcat-test-centers, Boise is located in western Idaho, located on the Boise River in a flat area, west of a 2,300-foot ridge. The urban area is at 700-800 meters altitude. The town of Boise forms the center of the conurbation, which extends westward over a flat agricultural area. Major sub-centers are Meridian, Nampa and Caldwell. The metropolitan area consists of two counties, Ada County with Boise and Meridian and Canyon County with Nampa and Caldwell. The urban area has not yet fully merged, but urbanization in the region is increasing rapidly.

Originally known as a drab town in the rural state of Idaho, Boise has been growing rapidly since the 1980s. The region has a robust and diverse economy and housing is much more affordable than in coastal cities. The region has weathered the recession as of 2008 as one of the best in the United States.

The region is growing rapidly. Ada County had only 70,000 residents in 1950, growing to 205,000 in 1990 and 512,000 in 2021. Adjacent Canyon County grew from 54,000 in 1950 to 90,000 in 1990 and 243,000 in 2021.

Road network

The Boise region has only two freeways, with Interstate 84 being the main one. The highway runs east-west through the urban area, connecting it to the Pacific Northwest (Portland, Seattle) and Utah (Salt Lake City). The highway has 2×2 to 2×4 lanes. Interstate 184 is a fork of I -84 and ends in downtown Boise. This highway has 2×3 lanes. The interchange between I-84 and I-184 is the only interchange in the region, but the link from Boise to Salt Lake City does have a 3-lane flyover, which is quite rare.

The only US Highway is the double -numbered US 20 and US 26, which runs east-west between Caldwell and Boise. US 95 passes north-south, well west of the metro area, but passes through Canyon County. Several State Highways pass through the region, none of which are highways.

Ada County is the only county in Idaho with its own Highway District, the Ada County Highway District (ACHD), which was established in the early 1970s. The ACHD manages approximately 3,400 miles of road, mostly urban and rural roads that are not State Highways, US Highways, or Interstate Highways.


Interstate 84 was numbered Interstate 80N before 1980, and was built throughout the Boise region in the 1960s. The I-184 was numbered as the I-180N. I-184 opened to traffic in 1968, completing the entire regional highway network as early as the 1960s.

Due to the rapid population growth since the 1980s, the highways have been widened. Until the early 1990s, I-84 still had 2×2 lanes through the Boise region. In the mid-1990s, I-84 was widened from I-184 to the west, first to 2×3 lanes, then to 2×4 lanes in 2003. In 2003, I-184 was also widened to 2×3 lanes. In the period 2009-2010, the corridor between Nampa and Meridian was widened to 2×4 lanes, so that I-84 has a longer stretch of 2×4 lanes. This often surprises local strangers, because Boise does not have a metropolitan image, many Americans still consider it a rural town.

Traffic intensities

In 2013, the busiest point was I-84 west of the I-184 interchange with up to 116,500 vehicles per day. The I-84 has more than 70,000 vehicles per day through the conurbation. I-184 peaked at a maximum of 72,000 vehicles per day.

Boise, Idaho