“Baggage transport tunnels are located underneath the Denver Airport.”

DEN uses a series of underground tunnels to run a passenger train to and from the terminal and three concourses. Parallel to the train are two miles of tunnels for golf carts and airline tugs to deliver bags, food and other supplies to the concourses. Most of the activity is related to baggage operations.

The truth is the airport property is more than twice the size of Manhattan (yes, it's that big) and requires miles and miles of underground infrastructure to protect its baggage system from Denver's snowy winters. The terminal train also runs through its own underground corridor. I took a golf cart ride all around the tunnels, which you need special access to, and it's set up like a proper road system with stop and yield signs and lanes.

“For years, rumors and urban legends have circulated about what actually happens under DIA… 9NEWS toured the tunnels of Denver International Airport to find out what is down there… At the end of the day, there is no military complex, no aliens or lizard people. It’s a lot of luggage down here… Everyday baggage operations happening underground.”

Although the airport acknowledges that there are several subterranean levels beneath the main terminal (including the trains that carry passengers to and from different concourses and a long-defunct automated baggage system), they say the tunnels only extend out to the perimeter of the airport, less than two miles.

For years, rumors and urban legends have circulated about what actually happens under DIA, Colorado's largest airport. 9NEWS reporter Briana Fernandez tours the tunnels of Denver International Airport to find out what is down there… {ts:43} "No military complex, no aliens or lizard people. It's a lot, a lot of luggage down here." {ts:57} "Well, it is a tunnel, a dark and dusty one filled with a whole lot of… it's really just thousands of workers a day going back and forth. The mysterious city theory has some truth to it. Everyday baggage operations happening underground."

As with most major airports, Denver International has infrastructure hidden from public view. Beneath the terminal is a sprawling network of service roads, a baggage-handling system and the tracks for the underground train that shuttles passengers between concourses. Airport officials say these tunnels and basements serve logistical needs, not secret societies or bunkers.

A facility the size of DIA requires a significant number of maintenance tunnels, not to mention the sheer amount of passenger baggage that needs to be moved around the airport.

“There really is a complex of tunnels and underground baggage transport systems beneath the airport. But these tunnels are used for moving luggage, freight and people—not for housing lizard people or secret bunkers. ‘We have an underground train system and baggage facilities and employee corridors,’ an airport spokeswoman said.”

“Deep in the bowels of Denver International Airport, in the underground chamber that houses the notorious $218.5 million automated baggage system, sits a woman with perhaps the most mind-numbing job in Denver… Perched on a metal chair in a mile-long tunnel that looks as wide as a four-lane highway… That ‘backup’ system, installed by Rapistan Demag Inc. for a paltry $63 million, moves baggage for all the airport’s carriers except United.”

DIA/DEN is known to have underground tunnels beneath the terminal for the passenger train system and for baggage and service carts. The airport’s own materials and multiple tours describe these tunnels as part of normal airport operations, not as secret facilities.

There are reportedly as many as 6 underground levels below the ground floor of DIA, and possibly more that are not even known about. Beyond that, there are theories that tunnels exist from the Colorado Springs Air Force Base to DIA and from the Air Force Base to the Cheyenne Mountain Complex in the Rocky Mountains outside of Colorado Springs. Also, while the airport was being built, 5 buildings were built below, but for some reason needed to be abandoned. Instead of destroying them, another infrastructure was built on top, leading many to wonder just what might be going on in those buildings underneath the ground level.

Many major airports operate extensive underground tunnel systems used for baggage handling, staff transport, and infrastructure. These tunnels allow bags, utilities, and workers to move beneath the terminal and airfield at hubs such as Denver International and Chicago O'Hare.

The podcast episode claims that beneath Denver International Airport lies more than ordinary infrastructure, suggesting that the underground tunnels and buried buildings may be used for secretive purposes beyond baggage and trains. It presents speculative ideas that the network under the runways could be part of a hidden facility rather than just a baggage system.

We are heading into the tunnels right now. Creepy. We are headed to the very end where the train that goes out to the concourse is dead ends. These tunnels include the remnants of the old baggage system when the airport was built.