The Nehalem River is a river on the Pacific coast of northwest Oregon in the United States, approximately 119 miles (192 km) long. It drains part of the Northern Oregon Coast Range northwest of Portland, originating on the east side of the mountains and flowing in a loop around the north end of the range near the mouth of the Columbia River. Its watershed of 855 square miles (2,210 km2) includes an important timber-producing region of Oregon that was the site of the Tillamook Burn. In its upper reaches it flows through a long narrow valley of small mountain communities but is unpopulated along most of its lower reaches inland from the coast.

Vernonia is a city in Columbia County, Oregon, United States. It is located on the Nehalem River, in a valley on the eastern side of the Northern Oregon Coast Range that is the heart of one of the most important timber-producing areas of the state. Logging has played a large role in the history of the city. The population was 2,151 at the 2010 census.