Formed February 7, 1889 (16th county)
Elmore County (28,665), Mountain Home (16,029)
The masonry and concrete Classical Revival courthouse for Elmore County was built in 1915. The structure is on East 4th Street between Jackson Street. United States Highway 30 is two blocks to the southwest. Wayland & Fennell were the designers of the courthouse. The county was created on February 7, 1889 from Alturas County, which no longer exists, as the 16th county. Rocky Bar was the original county seat with Mountain Home becoming the seat in 1891. The county is named for the Ida Elmore mines. The county seat is presumably a geographical term.
Elmore County government consists of a sheriff, a prosecuter, a coroner, a clerk, a treasurer, and an assessor (executive). It has 3 Commissioners (legislative.) Nine Circuit Court Judges and Two Magistrate Court Judges serve Elmore, Ada, Boise, and Valley counties (judicial.) The county is in southwest Idaho. Boise, Idaho is northwest and Twin Falls, Idaho is northeast of the county. The Snake River forms its southern border. The county center is 15 miles East of Mountain Home. The county is surrounded clockwise by Boise, Blaine, Camas, Gooding, Twin Falls, Owyhee, and Ada counties.
The area of the county is 3078 square miles. It is 6 out of 44 in the state. It ranks 13 out of 44 in population in the state. It has a density of 9.3 persons per square mile making it 23 out of 44 in the state. Elmore County has 60.4% of its population in its incorporated areas. Interstate Highway 84 crosses the county from southeast to northwest from Gooding County to Ada County. United States Highway 20 enters from Camas County, east, and joins Interstate Highway 84 into Ada County. United States Highways 26/30 are combined with Interstate Highway 84 from Gooding County to Ada County. The county has many zigs and zags but could be described as a small letter r facing backward. Mountain Home is in the southwest quarter of the county. Mountain Home is the county seat and the largest city. It is 55.9% of the county population. This county is in the Mountain Home Micropolitan Statistical Area.
Glenns Ferry
Mountain Home