The Cincinnati Subway was a planned mass transit system in Cincinnati, Ohio, USA however the project was never completed and today, the tunnels lie abandoned underneath the city. Many of its inhabitants have no idea that the tunnels exist beneath their feet.

Cincinnati was founded by Mathias Denman, Colonel Robert Patterson, and Israel Ludlow in 1788, first called Losantiville and changed to the present name in 1790. When steamboats begun service on the Ohio River in 1811, the city began to trade with St Louis and New Orleans. It was incorporated as a city in 1819 as the population grew rapidly. In 1827, the Miami and Erie Canal was completed and business in the city boomed. Immigration, notably by Irish and Germans, helped the city grow and by 1850, the population was 115,000.

The railways came to Cincinnati in 1836 and further fuelled local industry. The streetcar system was opened in 1859 with six lines and in 1889, the horse-drawn streetcars were replaced with electric streetcars. By this time, the Miami and Erie Canal had become unprofitable and had been abandoned. There was a proposal in 1883 to place a subway line along the canal bed and cover it with a wide boulevard. By the beginning of the 20th century, Cincinnati was one of the 7 largest cities in America and traffic congestion had become a major issue.

In 1910, plans for a rapid transit system were made and a route was chosen which included the canal bed and boulevard idea which had been mooted earlier. The route was to include a ring of the city as was popular in subway design at the time. An example of such a route is the Chemin de fer de Petite Ceinture in Paris. The city issued bonds worth $6 million to fund construction and put the plan to the citizens in a plebiscite. They voted yes to what had become known as The Loop however when the USA entered World War I, bond issues were banned and the plans were put on hold.

Despite the cost of the project doubling on price by the time the war had ended, the city decided to move forward with the subway system and construction began in January 1920. At the time, the city lacked the funds to construct the entire subway but planned to raise the money later. As construction continued, cracks began to appear in the foundations of buildings along the route and the city became burdened with litigation from owners. The money ran out with 11 kilometres (7 miles) of subway tunnels dug out but with no tracks laid.

Even with the eastern part of the loop removed from an updated plan, the cost of completion was estimated to be as high as $12 million. Central Parkway, the boulevard built on top of the subway line, opened in October 1928. As the city desperately tried to find funds to complete the project, the stock market crash of 1929 brought things to a grinding halted and the Cincinnatti subway was officially put on hiatus.

In 1936, the city commissioned a report into rapid transit in the city with a view to finishing the subway project but it advised against restarting construction. Debate continued until 1941 when the USA entered World War II and the attempts to revive the project were shelved. After the war, the City Planning Commission omitted the subway from its plans and in the 1950s, a water main was installed in one of the tunnels in an effort to save money digging a new one.

Over the years, there has been talk about different uses for the tunnels including a bottling plant, a fallout shelter, an underground mall and a night club. None of the proposals has come to fruition. In 2002, there was vote on a light rail system called MetroMoves which would have utilised the tunnels however it was voted down. In 2016 however, a new light rail line opened, originally called the Cincinnati Streetcar and later the Cincinnati Bell Connector.

For now, the Cincinnati Subway remains incomplete and abandoned but every couple of years, plans for the tunnels re-emerge. In the meantime, urban explorers continue to visit the underground system that many of the city’s residents are completely unaware of.

Location: Cincinnati, Ohio, USA

Abandoned: 1928