majority of it
The Columbia River forms a border between the states of Washington and Oregon.
The state south of British Columbia is Washington. Parts of Alaska are also south of British Columbia.
Washington is bordered by Oregon and Idaho.
Washington State is approximately 240 miles long from its northern boundary with Canada to its southern boundary with Oregon.
Columbia
The Columbia River
Columbia river
Columbia river
If you mean Oregon and Washington, you'd be looking for the Columbia River...
Columbia River
Washington and Oregon border the Columbia River.
The Columbia
The Columbia River.
The Columbia River separates Washington and Oregon. It runs from British Columbia, Canada, through Washington state, and forms part of the border between Washington and Oregon before emptying into the Pacific Ocean.
Columbia river
The Columbia River divides the states of Washington and Oregon. It flows north from its source in British Columbia, Canada, and empties into the Pacific Ocean. The river serves as a natural boundary between the two states for much of its length.
The Columbia River forms a major part of the border between the states of Oregon and Washington.