Ilwaco (/lwko/USdict:lwk) is a city in Pacific County, Washington, United States. The population was 936 at the 2010 census. Ilwaco was first settled by Henry Feister in 1851, and was named for Elwahko Jim, the son in law of Chief Comcomly. Ilwaco was officially incorporated on December 16, 1890. A narrow gauge railway, Ilwaco Railway and Navigation Company, ran for over thirty years. The railroad ran north up First Street in Ilwaco. A published photo shows the railroad's Ilwaco facilities, including a gallows turntable and elevated watering trough, were located on the southwest corner of the intersection of First and Spruce streets.

The depot was built nearby on Spruce Street. A siding was built for the Ilwaco Mill and Lumber Company. A published photo shows the passenger depot on the west side of First Street, at a point 14.8 miles (23.8km) from the Ilwaco Depot to Nahcotta. The Ilwaco freight depot was in a different building. The freight depot survived to modern times, and has been relocated to became part of the Ilwaco Heritage Museum. The train ran out on the dock in Ilwaco. Floating logs were stored behind log booms on the west side of the Ilwaco dock. At some point after 1890, First Street had been covered with wooden planks, and remained so until 1916, when it was paved over. By 1915, a published photo shows many more businesses along First Street.