The Columbia River
That would be the Columbia River. This river separates approximately two thirds of southern Washington from northern Oregon. At a place on the 46th parallel north this river total enters the state of Washington, and this parallel becomes the border line that separates the two states.
The Columbia River
The Columbia River separates Washington State and Oregon.
The Columbia River divides Washington and Oregon. The Columbia River is the largest river, at 1,240 miles, that flows into the Pacific Ocean.
There are many rivers that create state boundaries in the United States. The river that separates Washington from Oregon is the Columbia River.
The Pacific Ocean, Canada, Idaho, and the Columbia River separates us from Oregon
Washington and Oregon border the Columbia River.
If you mean Oregon and Washington, you'd be looking for the Columbia River...
The Columbia River.
Columbia River
The Grammart river flows north, and it is in Oregon.
columbia river