Forgotten underground: Incredible pictures of Chicago's abandoned, labyrinth tunnels once used to transport coal, ventilate movie theaters and hide phone cables

  • The Illinois Telephone and Telegraph Company built the expansive tunnel network around 1900 to hold cables
  • When they went bankrupt, the Illinois Tunnel Company took over and used the tunnels to move merchandise and coal
  • 62 miles of tunnels criss-crossed underneath the city
  • The tunnels were six feet wide and 7.5 feet high with one-foot thick concrete walls, powered by overhead trolley wires
  • Several theaters bought tunnel air to keep audiences cool

Chicago is famous for its soaring skyline, but hidden from view is a 62-mile grid of abandoned freight tunnels once considered an engineering masterwork.

Although the impressive grid connects all major railroad freight houses and many commercial establishments in downtown Chicago, few people ever saw this system from construction in 1899 to its abandonment in 1959.

It wasn't until a contractor kicked a hole into the side of the one of the bores during the 1992 floods that the doomed passageways became big news. 

Out of business: Almost a century after construction, the doomed Chicago tunnels had helped facilitate the Chicago Flood of 1992, despite chief engineer George W. Jackson¿s original intention that measures to prevent flooding be maintained

Chicago: The Illinois Telephone and Telegraph built the first 26 miles of this concrete tunnel by 1905. But the Illinois Tunnel Company which took over, building another 60 miles, went bankrupt in 1909 and construction stopped

Multi-purpose: In 1912, the Chicago Tunnel Company started using the track to move merchandise, coal and ash before abandoning the unprofitable tunnels in 1959

In 1899, Illinois Telephone and Telegraph laid narrow-gauge railway in underground tunnels to help it excavate the tunnels, according to The Weather Channel.

Under the watchful eye of chief engineer George W. Jackson, the company built the first 26 miles of tunnel to hold telegraph and telephone cables.

In 1905, the Illinois Tunnel Company took over construction, expanding the network to 60 miles before it went bankrupt in 1909.

The network, widely considered cursed, was taken over by the Chicago Tunnel Company which sold the communication installations and cables but continued to use the track to move merchandise, coal and ash in 1912. The group was finally forced to abandon the unprofitable tunnels in 1959.

Electric cars for hauling mail: The two-foot gauge Illinois Tunnel Company U.S. Mail car waiting at the platform of Grand Central Station in front of a Pere Marquette U.S. Mail car

Original plans: This City of Chicago subway plan was never built

Labyrinthine: This sectional view of the Illinois Tunnel Company's abandoned tunnels show tracks diverging at various points

On its way: This freight, reportedly made by Kilbourne & Jacobs, leaves Marshall Field & Company's basement

While the grid wasn't profitable, it was versatile.

The constant underground air temperature of 55 degrees Fahrenheit led to a curious second line of business — air conditioning. Several movie theaters bought tunnel air to keep audiences cool.

After it was abandoned, many Chicagoans forgot about the concrete tunnels until April 1992 when one of them under the Chicago River near Kinzie Street was punctured, flooding most of the system and two dozen downtown buildings with open tunnel connections.

Today, some sections of the tunnels are used for utility and communication lines.

Inventive: The constant underground air temperature of 55F led to a second line of business ¿ air conditioning. Several theaters bought tunnel air to keep audiences cool

Split: The original caption described this 1904 image as 'a typical street intersection'

Opening of Chicago subway for freight traffic: On July 7, 1905, an 11-car train was dispatched from the Erie freight house. These five cars were delivered to the Milwaukee freight house and the elevator in the foreground goes down to the tunnel

Mysterious: This three-way intersection at Congress and Franklin Streets in Chicago in 1902 looks empty and eerie

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