Benge is an unincorporated community in Adams County, Washington, in the United States. Because it is not tracked by the U.S. Census, a Census population estimate is not available. Benge is assigned the ZIP code 99105. The town is served by the Benge School District, and downtown Benge contains Benge Elementary School.At the 2000 census, the Benge ZIP code had a population of 57 persons, with 33 housing units. The median household income was $37,500.The Mullan Military Road, started in 1859 by Lieutenant John Mullan, connected the upper navigable Missouri River with the Columbia River. This 624-mile road, which passed through what was later to become the town of Benge, was completed in 1862 at a cost of $280,000. The Benge section of the road was completed on May 22, 1861; the wagon ruts were still visible in 2008 just northeast of town at the site of the First Benge School.