| Bonneville Mountain | |
| Elevation Ft: | 8140. |
| Elevation Ref: | [1] |
| Prominence Ft: | 40 |
| Prominence Ref: | [2] |
| Isolation Mi: | 1.68 |
| Etymology: | Benjamin Bonneville |
| Map: | Oregon#USA |
| Map Size: | 260 |
| Label Position: | left |
| Location: | Eagle Cap Wilderness |
| Country: | United States of America |
| State: | Oregon |
| Region: | Wallowa |
| Region Type: | County |
| Range: | Wallowa Mountains |
| Coordinates: | 45.2438°N -117.2099°W |
| Coordinates Ref: | [3] |
| Topo: | USGS Aneroid Mountain |
| Easiest Route: | scrambling east side[4] |
Bonneville Mountain is an 8140adj=midNaNadj=mid mountain summit located in Wallowa County, Oregon, US.
Bonneville Mountain is located eight miles south of Joseph, Oregon, in the Wallowa Mountains. It is set within the Eagle Cap Wilderness on land managed by Wallowa–Whitman National Forest.[2] The peak is situated south of Wallowa Lake and precipitation runoff from the mountain drains west into West Fork Wallowa River and east into the East Fork. Topographic relief is significant as the summit rises over 3700abbr=offNaNabbr=off above the lake in approximately three miles.
This landform's toponym was officially adopted in 1925 by the United States Board on Geographic Names to honor Benjamin Bonneville (1796–1878), an officer in the United States Army and explorer of the American West noted for his expeditions to the Oregon Country.[3] Captain Bonneville and his party are credited with the first documented entry into the Wallowa Valley by a non-native in 1834.[5] This mountain was originally known as Middle Mountain.[6]
Based on the Köppen climate classification, Chief Joseph Mountain is located in a subarctic climate zone characterized by long, usually very cold winters, and mild summers.[7] Winter temperatures can drop below −10 °F with wind chill factors below −20 °F. Most precipitation in the area is caused by orographic lift. Thunderstorms are common in the summer.