Welcome to Chattanooga...railroad closed! On July 29-30, 2018, a small army of CSX, NS, and contract crews were given a complete 48-hour shutdown of the 23rd Interlocking through which CSX's W&A Subdivision crosses the NS mainlines bound for Birmingham, AL and Memphis, TN. A complicated 2 tracks (CSX) crossing 3 (NS) diamond with movable points is being replaced by a series of crossovers which reduces the crossing to one crossing two, along with a new connection track between the two railroads. The new "zig zag" pattern of the interlocking can be seen in the distance. The old style Southern signal in the foreground and very wide signal bridge in the background were dismantled and replaced with newer PTC-compliant signals, and the East End and Main St. control points were eliminated on CSX.