6 Hidden Tunnels You Never Knew Were Beneath This Popular Illinois City

This system of passageways connects about 50 office buildings, shopping centers, parking areas, and train stations in the Chicago downtown area. It stretches more than five miles and links 40 blocks, allowing savvy Chicagoans to remain underground while exploring the Loop.

Portions of Chicago's infamous above-ground train lines are actually below the city. You will find access to portions of the Red and Blue lines by going deep into the Chicago tunnels.

Constructed in the early 20th century, these tunnels were used to transport all sorts of items from phone lines to mail on small electric trains. They were abandoned in 1959 for more efficient infrastructure and flooded during a construction project in the 1990s.

Both the water tower and tunnel were built in 1866 to bring fresh water from Lake Michigan to the people of Chicago. These were some of the only structures to survive the Great Chicago Fire.

5. The Deep Tunnel
Spanning 110 miles, this is one of the largest and longest civil engineering projects in American history, and most Chicagoans don't even know that it exists 365 feet below them. The point of the tunnels is to minimize the risk of flooding as well as improve the quality of water in surrounding rivers.

6. Sewers
Below the streets and train stations are the sewers where no human would want to go. This is where the rats live in Chicago.

Subterranean streets like Lower Wacker Drive will also give you a look at the underbelly of the city. If you're getting around by car, this is the fastest way to zoom around.

The nightly menu is written on a tarot card at this unique speakeasy-style underground bar that makes for a fun stop if you're looking to get beneath the streets of the city. You'll find the entrance inside The Green Door Tavern.

The award-winning cocktail menu at this underground tiki bar will blow you away. You'll want to try one (or two) of everything. The atmosphere is what really sets this hot spot apart. Click here for more details about this exciting place to party.