Topography
Portland is located 60 miles east of the Pacific Ocean at the northern end of Oregon's most populated region, the Willamette Valley. Downtown Portland straddles the banks of the Willamette River, which flows north through the city center and consequently separates the east and west neighborhoods of the city. Less than 10 miles from downtown, the Willamette River flows into the Columbia River, the fourth-largest river in the United States, which divides Oregon from Washington state. Portland is about 100 miles upriver from the Pacific Ocean on the Columbia.