Boise, the capital of Idaho

Lewiston, the first capital

When Congress created the Idaho Territory in 1863, the first territorial governor, William H. Wallace, set up the government in Lewiston, at the meeting of the Snake and Clearwater rivers. Lewiston was then the main town of the northern mining districts and the gateway to the gold fields. The first territorial legislature met there, but it did not fix a permanent capital.

Gold moves south

Meanwhile, gold strikes in the Boise Basin in 1862 had drawn thousands of miners to southern Idaho. By the territorial census of September 1863, the Boise area far outnumbered the north. When the second territorial legislature met in Lewiston in 1864, the southern majority used its votes to make Boise the capital, effective December 24, 1864.

A seal carried under guard

Lewiston fought back. Its supporters challenged the law in court and placed the territorial records and seal under armed guard. For months the capital existed in Boise on paper while the government’s papers stayed in Lewiston. In the spring of 1865 the acting governor, C. DeWitt Smith, settled the matter: with soldiers from Fort Lapwai as an escort, he carried the seal and the archives out of Lewiston and arrived in Boise on April 14, 1865. The territorial supreme court later upheld the move. Boise remained the capital when Idaho became a state in 1890.

The Capitol

The Idaho State Capitol was designed by John E. Tourtellotte and Charles Hummel. The legislature authorized it in 1905, and the central section and dome were finished late in 1912. The House and Senate wings were added in 1919 and 1920, completing the building. From the first floor to the top of the copper eagle on its dome, it rises 208 feet. The eagle was regilded in 2005.

Most of the exterior is sandstone from Table Rock, a mesa east of Boise. The ten-ton blocks were hauled by inmates of the old Idaho Penitentiary nearby. Inside, the builders used marble from Georgia, Alaska, Vermont and Italy.

The Capitol is heated in an unusual way. Boise sits on a geothermal reservoir, and water from about 3,000 feet underground is pumped in to heat the building, making it the only geothermally heated state capitol in the country.

Boise today

Boise had about 238,000 residents in 2025, the largest city in Idaho. It is the center of a fast-growing metropolitan area that includes Meridian, Nampa and Caldwell. Lewiston, the first capital, is a much smaller city on the Washington border.

Visiting

The Capitol is open to the public, and the Idaho State Capitol Commission offers tours and visitor information on its website.