The Columbia River is the largest river in the Pacific Northwest region of North America forming in the Rocky Mountains of British Columbia, Canada. It flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean. Its drainage basin is roughly the size of France and extends into seven states of the United States and one Canadian province. The Columbia has the greatest flow of any North American river entering the Pacific and has the 36th greatest discharge of any river in the world.