The Arndt Prune Dryer is a specialized agricultural building in Ridgefield, Washington. Built about 1898, it is one of the last traditional farm-built prune dryer buildings in Washington, using a wood fire and natural draft to dry locally grown fruit. Prunes were a major crop in the Vancouver region, as the dried fruit could be shipped economically to markets without refrigeration or spoilage. The Arndt Prune Dryer was placed on the National Register of Historic Places on October 4, 1979. The surrounding lands still have mature prune trees, some planted in the 1890s.