2280 American Legion Blvd
Mountain Home, ID 83647
Mountain Home, ID 83647
Long before European and American explorers arrived, the land now known as Elmore County was home to the Shoshone and Bannock Tribes. These Indigenous communities followed seasonal food sources, spending winters along the Snake River and returning to the Camas Prairie in the spring.
They lived in extended family groups and relied on hunting, fishing, and gathering plants such as berries, roots, and the blue-flowered camas plant, which was a vital food source. Camas roots were harvested and prepared into dried cakes that could be stored and eaten throughout the year.
This seasonal and resource-based way of life continued for generations. However, significant cultural and lifestyle changes began with the arrival of explorers, trappers, and settlers.
In 1803, the United States expanded westward through the Louisiana Purchase, which included the region that would later become Idaho. President Thomas Jefferson sent explorers Meriwether Lewis and William Clark in 1804 to study the land and document resources.
Their reports of abundant wildlife, particularly beaver, attracted fur trappers. Early trappers associated with John Jacob Astor’s Pacific Fur Company traveled the Snake River and made early contact with local tribes. By the 1840s, heavy trapping had drastically reduced beaver populations.
During this period, interactions between trappers and Indigenous groups were generally peaceful. However, tensions increased as settlement expanded.
Between 1840 and 1862, more than 250,000 emigrants traveled west through present-day Elmore County along the Oregon Trail. One of the most dangerous parts of the journey was crossing the Snake River at Three Island Crossing, located near present-day Glenns Ferry.
Many travelers lost wagons, supplies, and livestock at this crossing. Today, Three Island Crossing State Park preserves this historic location and shares the stories of pioneer migration.
The discovery of gold in the early 1860s brought a population boom to southern Idaho. The region was part of Alturas County, one of Idaho’s original counties. Mining communities such as Rocky Bar and Atlanta quickly developed.
These mining camps attracted people from diverse backgrounds, including Civil War veterans, immigrants, merchants, and laborers. Chinese miners also played an important role in early mining operations despite facing discrimination and difficult working conditions.
Mining brought both prosperity and hardship, along with colorful stories and legendary figures such as “Pegleg” Annie Morrow, who survived a severe blizzard and later became a well-known community figure in Atlanta.
Farmers and ranchers soon followed miners into the region. Settlement increased as individuals claimed land and developed farms and ranches, a process known as “proving up” land.
Agriculture expanded rapidly, supported by transportation routes and mining communities needing food and supplies. Crops included fruit, grain, and livestock such as cattle, sheep, and horses.
Basque immigrants from the Pyrenees Mountains of Europe became especially important to the sheep industry and contributed significantly to the county’s cultural heritage.
As communities such as Mountain Home and Glenns Ferry grew, residents advocated for a new county with a centrally located seat of government. Elmore County was officially created on February 7, 1889, and Mountain Home became the permanent county seat in 1891.
The late 1800s and early 1900s brought major growth, especially after completion of the Oregon Short Line Railroad, which allowed local agricultural and mining products to reach national markets.
Economic challenges during the Great Depression slowed growth, but prosperity returned during World War II with the construction of Mountain Home Air Force Base. The base remains the county’s largest employer and has significantly influenced local economic development and cultural diversity.
Today, Elmore County continues to grow while maintaining strong ties to its historical roots in agriculture, military service, and outdoor recreation.
Elmore County is located in southwestern Idaho and covers more than 3,000 square miles. It is bordered by:
Boise County (North)
Blaine, Camas, Gooding, and Twin Falls Counties (East)
Owyhee County (South)
Ada County (West)
Approximately 60% of the county is mountainous, while 40% consists of the Snake River Plain. Elevations range from 2,500 feet to over 9,700 feet.
Nearly 70% of county land is managed by federal agencies, including the U.S. Forest Service, Department of Defense, and Bureau of Land Management. About 22% of the land is used for agriculture.
Major transportation routes include:
Interstate 84 – Primary east-west highway connecting the region to Salt Lake City and beyond
U.S. Highway 30 – Historic transportation route
State Highways 20, 51, and 67 – Provide access throughout southwestern Idaho
Highway 67 connects Mountain Home directly to Mountain Home Air Force Base.
Major water features include:
Snake River – Southern boundary of the county
Boise River – Northern boundary
C.J. Strike Reservoir
Anderson Ranch Reservoir
These water sources support agriculture, recreation, and wildlife.
Temperatures vary widely across the county due to elevation differences:
Mountain Home: -36°F to 110°F
Atlanta: -19°F to 101°F
Atlanta: Approximately 21 days
Mountain Home: Approximately 136 days
Glenns Ferry: Approximately 143 days
Summer months have an 80–85% chance of sunshine.
Winds are generally mild, with strongest winds typically occurring in late winter and spring.
Winter inversions occasionally trap cold air and pollutants, though they usually clear quickly.
Elmore County offers a wide range of outdoor recreation opportunities.
Boise National Forest
Sawtooth National Forest
Activities include hiking, camping, backpacking, fishing, and wildlife viewing.
Located in Glenns Ferry, this park preserves an important Oregon Trail crossing and features educational exhibits and historic wagon ruts.
Home to some of North America’s tallest sand dunes, formed thousands of years ago. Visitors enjoy hiking, wildlife viewing, and photography.
Popular boating locations include:
Anderson Ranch Reservoir
C.J. Strike Reservoir
Both offer boating access, fishing, and sailing events.
More than 250 developed campsites exist throughout the county, ranging from RV hookups to primitive camping.
Elmore County offers excellent opportunities for anglers and hunters. Common fish species include trout, bass, catfish, and kokanee salmon. Wildlife hunting opportunities include deer, elk, upland birds, and waterfowl.
Winter activities include:
Downhill skiing at Soldier Mountain Ski Area
Cross-country skiing
Snowmobiling
Elmore County was built on exploration, resourcefulness, and community growth. While industries and lifestyles have changed over time, the county continues to offer opportunities in agriculture, military service, recreation, and economic development.