Cincinnati Subway, Ohio

For nearly a century, the Miami and Erie Canal cut through Cincinnati, dividing the Over-the-Rhine neighborhood from downtown. By the early 1900s, the canal was obsolete, and the city had a bold idea: drain it, and use the empty canal bed for a subway. In 1916, voters approved a $6 million bond issue, by a 6-to-1 margin, to build a rapid transit loop of about 16 miles around the city. The subway section would run in the old canal bed, and a new boulevard, Central Parkway, would be built on top. Then World War I intervened. Lawsuits and the war delayed the work, and while the city waited, construction costs soared. On January 28, 1920, the first steam shovel finally bit into the canal bed at Walnut Street. Crews built the main subway tunnel in four contracts between 1920 and 1923, about two miles long, with underground stations at Race Street, Liberty Street and Brighton. They also graded miles of above-ground route and built short suburban tunnels, bridges and several surface stations. By 1925, the $6 million was gone. The tunnels were dug, but there was no track, no power system, no finished stations and no subway cars. In October 1928, Central Parkway opened on top of the empty tubes, and that same year, the subway project was indefinitely shelved. Over the decades, the city considered reviving it several times, but every attempt to put the tunnels into service failed. In the 1950s, much of the unfinished above-ground route was taken for the construction of Interstate 75, and its surface stations were demolished. The tunnels themselves survived. Cincinnati-Transit.net describes them as the largest abandoned subway tunnel in the United States. They've carried utility lines, and the city still inspects them. The Race Street station, the largest in the system, still sits beneath the median of Central Parkway, built for three tracks that were never laid.