Park development began in the early 1930s, with the work of Company 1743, an African-American company of the Civilian Conservation Corps. Their stonework is visible throughout in buildings, on trails and roadsides.

The park is in the central eastern part of the state one hour south of St. Louis on Hwy. 21,about 14 miles northeast of Potosi, five miles south of De Soto. Gas is available at the park entrance.

There are three trails that provide access to different habitats, including the Washington State Park Hardwood Natural Area; all rated rugged. 1000 Steps Trail is 1.5 miles; Opossum Track Trail is 2.5 miles; and, Rockywood Trail is 6 miles.