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Giant Network Of Tunnels Fills Chicago's Underground, History Books

 Underground tunnels in Chicago
Chicago underground tunnels
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DOWNTOWN — Deep in Chicago history — and deep under the city ground — lies a network of tunnels that was used for decades and is now all but impenetrable.

The tunnels were used for a variety of tasks from 1904-1959, according to Russell Lewis of Chicago History Museum. Those uses included deliveries from electric trains, which sent products to the Field Museum, City Hall, Chicago Tribune and other iconic city buildings.

In total, 60 miles of tunnels were built starting in 1899 by the Illinois Telephone and Telegraph Company, which later became the Chicago Tunnel Company. The tunnel company created "tunnel air," which was pumped into city buildings like air conditioning, according to atlasobscura.com. The website noted the clay soil removed by hand that made the tunnels was used to build up "low lying areas on the waterfront."

"Chicago’s tunnel system, which winds 60 miles through the Loop and north and west of the river, represents the city’s expanding infrastructure on the cusp of the 20th century and the vexing problem of where to put telephone wires — and make them accessible for repairs and upgrades — that would connect the city through electronic communication," Lewis said.

"The tunnels also provide a clue to the life of the city that occurs below the street — in the water pipes, sewer pipes, gas pipes, electrical wiring, communication wiring and fiber optics cables — that help to provide basic comforts and amenities to millions of Chicagoans."

Chicago Tunnel Company went out of business in 1959, but the tunnels were still used by the Tribune, according to atlasobscura.com, which through 1981 transported "newsprint from their paper warehouse to Tribune Tower."

Last month was the 25th anniversary of the "Great Chicago Flood," when 124 million gallons of Chicago River water poured into the tunnels after "a private contractor had driven new wooden pilings into the river bed next to the Kinzie Street drawbridge to protect the bridge from passing barges and other traffic on the North Branch of the Chicago River. The pilings had been placed in the wrong spot and punctured the ceiling of the freight tunnel below," according to the Tribune.

For the last quarter-century-plus, the tunnels have been sealed with entry "near impossible," according to atlasobscura.com.

"Few of us walk the streets with any knowledge of the activity and the history of Chicago that lies beneath our feet," Lewis said.

Check out some old-school photos of the tunnels in the slideshow above.