Idaho: Other Historic Sites

A list of important historic sites in Idaho.

Assay Office

Location: Boise, Ada County

Relevant issues: Business and industry

Statement of significance: Built by the federal government in 1870-1871, the Boise Assay Office illustrates the importance of mining in the political, social, economic, and legal development of Idaho and the Far West. In operation from 1872 to 1933, it is one of the most significant public buildings remaining from Idaho’s territorial days.

Bear River Massacre Site

Location: Southeastern Idaho

Relevant issues: American Indian history, military history

Statement of significance: On January 29, 1863, California Volunteers under the command of Colonel Patrick Edward Conner attacked a band of Northwestern Shoshone. The bloodiest encounter between Native American and white men to take place in the West in the years between 1848 and 1891, Bear River Massacre resulted in the deaths of almost three hundred Shoshone and fourteen soldiers.

Camas Meadows Battle Sites

Location: Kilgore, Clark County

Relevant issues: American Indian history, military history

Statement of significance: On August 19, 1877, the military force led by Major General Oliver Otis Howard which had been pursuing the Nez Perce since their departure from Clearwater was in a position to intercept them in their flight to Canada. Here, on August 20, a predawn raid by Nez Perce warriors succeeded in capturing most of Howard’s pack mules, forcing the army to halt until more mules and supplies could be secured, which resulted in a time-consuming detour. The army’s delay made it possible for the Nez Perce to escape into Yellowstone Park and Montana. Their remarkable journey toward Canada continued six weeks longer as a result of this raid.

Cataldo Mission

Location: Cataldo, Kootenai County

Relevant issues: American Indian history, religion

Statement of significance: The oldest extant mission church in the Pacific Northwest, Cataldo was used by Jesuit missionaries (1850 or 1853) in their efforts to convert the Coeur d’Alene Indians.

City of Rocks

Location: Almo, Cassia County

Relevant issues: Western expansion

Statement of significance: A popular stopping point on the California Trail named for its strange resemblance to a city skyline scattered across Graham and Circle Creeks and their basins and rising against a backdrop of wooded mountainsides, this complex provided westbound emigrants a refreshing contrast to the extensive sagebrush plains surrounding it. Thousands of emigrants camped here, leaving still-visible wagon rut tracks. The site is now a state park and a national reserve.

Experimental Breeder Reactor No. 1

Location: Arco, Butte County

Web site:

Relevant issues: Science and technology

Statement of significance: On December 20, 1951, the EBR-I produced the first usable amounts of electricity created by nuclear means; in July, 1963, it was the first reactor to achieve a self-sustaining chain reaction using plutonium instead of uranium as the major component in the fuel. In addition, the EBR-I was the first reactor to demonstrate the feasibility of using liquid metal at high temperatures as a reactor coolant.

Fort Hall

Location: Fort Hall, Bannock County

Relevant issues: Western expansion

Statement of significance: Fort Hall is the most important trading post in the Snake River Valley and is known for its important association with overland migration on the Oregon-California Trails. In the 1860’s and 1870’s, it was a key road junction for the overland stage, mail, and freight lines to the towns and camps of the mining frontier in the Pacific Northwest.

Lolo Trail

Location: Lolo Hot Springs, Clearwater County

Relevant issues: Western expansion

Statement of significance: When, after reaching Lehmi Pass and crossing the Continental Divide, navigation of the Salmon River proved impossible, Meriwether Lewis and William Clark determined to use one of several trails over the mountains used by the Nez Perce in their annual journeys to the buffalo plains in the east. The Lolo Trail, used by the explorers to cross the Bitterroot Mountains in September, 1805, represents probably the most arduous single stretch of the entire route traveled by the expedition.

Weippe Prairie

Location: Weippe, Clearwater County

Relevant issues: American Indian history, western expansion

Statement of significance: On the morning of September 20, 1805, an advance party of the Lewis and Clark Expedition came out of the Bitterroot Mountains onto the southeastern corner of Weippe Prairie, the western terminus of the Lolo Trail and long a favored source of camas root for the Nez Perce Indians. Here, the expedition first met the Nez Perce, who had never before seen white men. The Nez Perce gave the explorers food as well as much-needed help and directions during the two-and-a-half-week period spent in their territory.