Cowan Tunnel
From Wikipedia The tunnel was built by the Nashville & Chattanooga Railroad Company and was completed in 1852 with the tracks laid in 1853. The strategically important tunnel, part of the rail linkage between the Midwestern United States and the Southeastern United States, played a vital role during the American Civil War. It was considered a major engineering feat at the time. It is still operational and owned by CSX Railroad.
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