Malheur County (, ) is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 31,571. Its county seat is Vale, and its largest city is Ontario. The county was named after the Malheur River, which runs through the county. The word "malheur" is French for misfortune or tragedy. Malheur County is included in the Ontario, Oregon Micropolitan Statistical Area, which is also included in the Boise Combined Statistical Area. It is included in the eight-county definition of Eastern Oregon.
History
Malheur County was created , from the southern territory of Baker County. It was first settled by miners and stockmen in the early 1860s. The discovery of gold in 1863 attracted further development, including settlements and ranches. Basques settled in the region in the 1890s and were mainly engaged in sheep raising.
Geography
According to the United States Census Bureau, the county has a total area of , of which is land and , comprising 0.4%, is water. It is the second-largest county in Oregon by area and the only county in Oregon in the Mountain Time Zone.thumb|800px|Pillars of Rome, from [[U.S. Route 95|US 95 near Rome|none]]
Adjacent counties
- Grant County - northwest/Pacific Time Border
- Baker County - north/Pacific Time Border
- Washington County, Idaho - northeast
- Payette County, Idaho - east
- Canyon County, Idaho - east
- Owyhee County, Idaho - east
- Humboldt County, Nevada - south
- Harney County - west/Pacific Time Border
National protected areas
- Deer Flat National Wildlife Refuge (part)
- Malheur National Forest (part)
- Whitman National Forest (part)
Highways
Railroads
The main railroad in Malheur County is the Oregon Eastern Railroad. This line goes from Ontario to the Celatom Plant in Vale. This railroad is all that remains of the Wyoming Colorado Railroad, a short line between Colorado, Wyoming and Oregon.OERR locomotive at [[Vale, Oregon|Vale|thumb|330px|none]]
Time zones
alt=Map of Malheur County|thumb|Map of Malheur County thumb|Most of Malheur County (shown in purple) is in the [[Mountain Time Zone; a small portion in the southern part of the county is in the Pacific Time Zone along with the rest of the state of Oregon and neighboring Nevada.]]
As with many cities, Malheur County's cities had functioned with both city time and railroad time. This changed by order of the Interstate Commerce Commission on May, 13th 1923 with cities adopting train time. Malheur County is still one of the few counties in the United States with two time zones. Most of the county is in the Mountain Time Zone, but a small portion in the south is in the Pacific Time Zone, indicative of that area's proximity to its main service town, Winnemucca, Nevada.