The Green River Tunnel is a pair of 1,138.2-foot (346.9 m) vehicular tunnels that carry Interstate 80 /U.S. Route 30 through Castle Rock, a sandstone ridge in Green River in Sweetwater County, Wyoming, United States. The two tunnels, one for eastbound and one for westbound traffic, opened on October 28, 1966. The tunnels run approximately from mile points 90.1 to 90.3 along the interstate.