The tunnel is 1600 feet long. It was in service from 1891 to 1982 along the Pigeon Mountain route and was originally a part of the Estelle Mining Company Railroad. It joined the Chattanooga Southern Railway just NW of the tunnel. Later on the railway would be named the Tennessee, Alabama, and Georgia Railway, or TAG. The tunnel and that section of rails were abandoned after Norfolk Southern. This tunnel is easy to get to, albeit pretty well hidden. It's in a decaying state and there's several spots where water pours through cracks in the ceiling.