The Article of the day for July 18, 2017 is Columbia River . The Columbia River is the largest river in the Pacific Northwest region of North America. Rising in the Rocky Mountains, it flows south into Washington, then turns west to form most of that state's border with Oregon before emptying into the Pacific, 1,243 miles (2,000 km) from its source. By volume it is the fourth-largest river in the US and the largest in North America that enters the Pacific. The river system hosts salmon and other fish that migrate between freshwater habitats and the saline waters of the Pacific Ocean. In the late 18th century, a private American ship became the first non-indigenous vessel to enter the river. Overland explorers entered the Willamette Valley through the scenic but treacherous Columbia River Gorge. Railroads were built in the valley in the late 19th century, many running along the river. Since the early 20th century, the river has been dammed for power generation, navigation, irrigati...