Raystown Lake is a reservoir in Huntingdon County, Pennsylvania. It is the largest lake that is entirely within Pennsylvania. The original lake was built by the Simpson family of Huntingdon as a hydroelectric project. The current 8,300-acre (34 km2) Raystown Lake was completed in 1973 by the Army Corps of Engineers. Raystown is around 200 feet (61 m) deep in the deepest area near the dam. The lake was created primarily to control floods, provide electricity, and support recreational activities. Allegheny Electric Cooperative operates the Raystown Hydroelectric Project and William F. Matson Generating Station at the Raystown Dam,a 21 MW, two-unit hydroelectric project.