Blue Mountains (Pacific Northwest)
The Blue Mountains are a mountain range in the western United States, located largely in northeastern Oregon and stretching into southeastern Washington. The range has an area of 4,060 square miles (10,500 km2), stretching east and southeast of Pendleton, Oregon, to the Snake River along the Oregon-Idaho border. The Blue Mountains cover seven counties in Oregon and Washington; they are Union, Umatilla, Grant, Baker, and Wallowa counties in Oregon, and Walla Walla, Columbia and Garfield counties in Washington. They are home to the world's largest organism and fungal mycelial mat, the Armillaria solidipes.
The Blues are uplift mountains,.
Geologically, the range is a part of the larger rugged Columbia River Plateau, located in the dry area of Oregon east of the Cascade Range. The highest peaks in the range include the Elkhorn Mountains at 9,108 feet (2,776 m),Strawberry Mountain at 9,038 feet (2,755 m), and Mount Ireland at 8,304 feet (2,531 m). The nearby Wallowa Mountains, east of the main range near the Snake River, are sometimes included as a subrange of the Blue Mountains.
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