TAG Tunnel This abandoned and neglected tunnel was built in 1890-91 by the Chattanooga Southern Railroad through the northern tip of Pigeon Mountain in Walker County. The mountain, actually an arm of the Lookout Mountain plateau, dominated a particularly scenic part of the line, prompting the railroad to market itself as the "Pigeon Mountain Route." In 1911, the Chattanooga Southern was reorganized as the Tennessee, Alabama, and Georgia Railway, which became known by the nickname "TAG Route." Southern Railway purchased the line in 1971 and operated it for a little over a decade before abandoning the middle section, which included the tunnel, in the early 1980s. An old advertisement for the Pigeon Mountain Route featured a romanticized view of the tunnel promoting the railroad's picturesque and historic mountain and valley scenery. Georgia's Railroad History & Heritage. Copyright, Steve Storey. Railroad History | The Depot List | Locomotives On Display | Odds & Ends | Sources & References | Home