The MacArthur Tunnel, formally known as the General Douglas MacArthur Tunnel, is a highway tunnel located on the grounds of The Presidio of San Francisco (which is now part of the Golden Gate National Recreation Area) in San Francisco, California. It carries California State Route 1 under a large hill at the Presidio Golf Course, and connects Park Presidio Boulevard to US 101 on the Golden Gate Bridge Freeway (better known as Doyle Drive).