People having spent years speculating about the labyrinth of underground baggage tunnels beneath the airport, fueling talk of elite bunkers and lizard‑people.

Now, the airport will repurpose the tunnels and turn them into walkways for pedestrians that will connect three separate concourses.

A sign outside the Denver International Airport thanks federal employees on November 8, 2025. | Michael Ciaglo/Getty Images

Denver International Airport Announces Pedestrian Walkways

Denver International Airport has announced that the tunnels will be opened to the public as a walkable alternative to the current train system, providing an alternative option for passengers traveling between concourse A, B and C.

It comes as the airport has invested over $75 million into modernizing its train systems, with more new train cars and other upgrades still to come.

What Denver International Airport Has Said

In a press release, the airport CEO Phil Washington said: "As DEN continues to increase passenger numbers and global connections, we are committed to providing customers with the best airport experience. Adding pedestrian walkways to DEN’s current infrastructure is another key component of our Vision 100 plan."

Mayor of Denver Mike Johnston also spoke about the project, calling it a "big win" for travelers and the community alike. He also subtly addressed the conspiracy theories.

"These new pedestrian walkways would deliver on that—giving folks more flexibility while we continue building one of the best-connected airports in the world," he said.

"And who knows…maybe along the way, travelers will finally get a closer look at the underground tunnels and decide for themselves what’s fact and what’s fiction," Johnston added.

The announcement has quickly sparked online interest, with the political commentator Mario Nawfal writing in a post on X that has been viewed over 16,000 times: "The tunnels have fueled conspiracy theories about secret bunkers and lizard people since the airport opened in 1995."

Denver Airport Conspiracy Theories Explained

Denver International Airport is surrounded by myths involving secret societies, aliens, underground bunkers, and ominous artwork. The airport has, over the years, leaned into jokes around the theories for marketing purposes.

In 2018, the airport launched a "DENFILES" campaign, which featured images of UFOs and green aliens. One advertisement read: "What are we doing," and listed three options: adding new bars and restaurants, remodeling a lizard's lair or building an Illuminati headquarters.

Then, in 2019, Denver International Airport and Roswell International Air Venter became "supernatural sister airports," a tongue‑in‑cheek partnership that includes a humorous clause about sharing extraterrestrial combat strategies.

This is what we know about some of the key conspiracy theories surrounding Denver International Airport.

Tunnels

Rumors claim the airport’s underground tunnels hide elite bunkers, alien habitats, lizard‑people lairs, or military bases. In reality, they’re baggage‑handling tunnels, though employee pranks and graffiti have fueled the myths.

New World Order and Secret Societies

A time‑capsule plaque with a Masonic symbol and the phrase "New World Airport Commission" sparked claims that the airport is controlled by Freemasons or tied to the New World Order. The airport says the Freemasons simply designed the plaque, and the wording references Dvořák’s New World Symphony, not a secret group.

Blue Mustang ('Blucifer')

The 32‑foot blue horse statue with glowing red eyes that greets visitors to the airport is sometimes described as demonic or linked to the Four Horsemen of the Apocalypse. Its glowing eyes are a tribute to the artist’s father, who worked with neon lighting.

File photo: The 32-foot fiberglass sculpture "Blue Mustang," also known as "Blucifer," greets visitors at Denver International Airport in this image t... | George Rose/Getty Images

Nazism

Some interpret airport artwork as depicting Nazi imagery or apocalyptic prophecy. Its temporary removal during construction intensified speculation. Claims that the runways form a swastika are disproved by aerial photos.

Alien Languages

Strange symbols around the airport are often said to be alien writing. They are actually Navajo characters and artist identifiers, not extraterrestrial messages.

Flat Earth

A 2023 TikTok video claimed Old World‑map artwork at the airport was new evidence supporting flat‑earth theory. The claim was quickly debunked.

Gargoyles

The airport features playful gargoyle statues meant to "protect" luggage. An animatronic gargoyle named Gregoriden jokingly referenced conspiracies ("Welcome to Illuminati headquarters"), which some found unsettling, leading to a toned‑down replacement.

What Happens Next

The airport has long insisted that the tunnels are less than two miles long.

Details of the tunnel project are currently being finalized, and construction is expected to begin in 2027.