Ridgefield is a city in northern Clark County, Washington, in the United States. The population was 4,763 at the 2010 census.
Located within the Portland metropolitan area, Ridgefield is notable for the significant Native American archives and link to the Lewis and Clark Expedition. It is then the headquarters of the Ridgefield National Wildlife Refuge, a primary reserve for migrating waterfowl on the Pacific Flyway, and the home of the Ridgefield High School “Spudders” (reflecting the area’s potato-farming heritage).

The Place has important ties to the Lewis and Clark Expedition of 1804–1806, being close to the Chinookan town of Cathlapotle, then a unity of 700–800 people, with at least 14 substantial plank houses. The community’s ties to the Chinookan people was commemorated by the construction of a replica of a Cathlapotle plank home at the handy Ridgefield National Wildlife Refuge, which was dedicated March 29, 2005.

The town was formerly known as Union Ridge, named by the many Union veterans in the midst of the first large greeting of settlers after the Civil War and was renamed Ridgefield in 1890. The town’s indigenous name is preserved in the reveal of Union Ridge Elementary School.^{[citation needed]}

Ridgefield was an important trading center as to the fore as the 1860s later than its key location close the mouth of the Columbia River, and the city was officially incorporated upon August 26, 1909. U-Haul, an American equipment rental company, had its Begin in Ridgefield in 1945.

According to the United States Census Bureau, the city has a total area of 7.18 square miles (18.60 km²), of which 7.08 square miles (18.34 km²) is estate and 0.10 square miles (0.26 km²) is water.