The Grande Ronde River ( or, less commonly, ) is a 210-mile (340 km) long tributary of the Snake River, flowing through northeast Oregon and southeast Washington in the United States. Its watershed is situated in the eastern Columbia Plateau, bounded by the Blue Mountains and Wallowa Mountains to the west of Hells Canyon. The river flows generally northeast from its forested headwaters west of La Grande, Oregon, through the agricultural Grande Ronde Valley in its middle course, and through rugged canyons cut from ancient basalt lava flows in its lower course. While it joins the Snake River ...
Click any point for details. Sections without stored geometry are drawn as straight put-in → take-out lines — actual courses follow the river.