September 2025. After Oscar came to London in June 2024 and I joined him there for a day, I’m now going to his hometown of Denver in Colorado. My second trip to the United States in 2025, after visiting my uncle and aunt in Wilmington, North Carolina. No, Denver is is not on foreign tourists’ mind when travelling to the US. But that doesn’t bother me. Quite the contrary. 

Denver International Airport, with IATA code DEN, is a major public airport serving the Denver metropolitan area, and lies about 25 miles (around 40 kilometres) northeast of downtown Denver. It opened on 28 February 1995, replacing Stapleton International Airport. 

Covering 33,531 acres, equivalent to about 52.4 square miles or 135.7 square kilometres, it is the largest airport in the Western Hemisphere by land area and the second largest in the world. At an elevation of 5,434 feet (1,656 metres), it requires special consideration for aircraft performance due to thinner air at altitude.

The airport has six runways, including the longest public-use runway in North America, which measures 16,000 feet (4,877 metres). This enables it to handle the largest commercial aircraft even under ‘hot and high’ conditions. United Airlines uses Denver as a major hub, while Frontier and Southwest Airlines also operate significant services there.

Its central passenger facility is the Jeppesen Terminal, named after aviation pioneer Elrey Borge Jeppesen. This striking structure is instantly recognisable by its white, peaked fabric roof, designed to evoke both the Rocky Mountains and Native American teepees. 

Three midfield concourses—A, B and C—house more than 160 gates. Concourse A handles most international flights, while United operates primarily out of Concourse B and Southwest out of Concourse C. An underground train links all concourses with the terminal, though Concourse A can also be reached by a pedestrian bridge.

The airport has undergone major expansions in recent years, with additional gates built and security facilities reconfigured to improve passenger flow. Long-term plans, known as ‘Operation 2045‘, envision further concourses and up to 100 new gates, allowing the airport to serve more than 125 million passengers annually.

Passenger numbers continue to grow, with over 82 million travellers passing through in 2024. Denver now ranks among the busiest airports in the world, offering non-stop flights to more than 230 destinations across the Americas, Europe and Asia. It is the largest single employer in Colorado, with more than 40,000 staff, and plays a vital role in the state’s economy.

Over the years, Denver has faced challenges. Its automated baggage system, initially intended as a state-of-the-art solution, became infamous for cost overruns and malfunctions before being abandoned. Severe winter weather has also caused major disruptions, though the airport has invested heavily in snow removal to reduce closure times. 

There have been notable incidents, including a 2021 engine failure on a United Airlines flight that scattered debris across a nearby suburb.

Beyond operations, the airport has a vibrant cultural identity shaped by its art. 

The giant blue horse statue with glowing red eyes, officially titled ‘Blue Mustang‘ but popularly nicknamed ‘Blucifer‘, has become one of its most notorious symbols. Murals by artist Leo Tanguma, filled with vivid imagery, aim to convey messages of peace and environmental harmony but have sparked much interpretation and controversy.

Because of its immense size, distinctive architecture, cost overruns and unusual art, Denver International Airport has long been a magnet for conspiracy theories. While largely unfounded, they remain part of the airport’s mythology, adding to its reputation as one of the most distinctive airports in the world.

Conspiracy theories

Denver International Airport is almost as well known for the stories that surround it as for its role as a major aviation hub. Since it opened in 1995, it has become the subject of a wide range of conspiracy theories, fuelled by its enormous size, construction delays, budget overruns and unusual design features.

One of the most persistent beliefs is that there are vast underground bunkers and tunnel systems hidden beneath the airport. 

While it is true that tunnels exist for baggage handling and passenger transport, conspiracy theorists claim that these extend far beyond their intended use, supposedly linking to secret government facilities or serving as survival shelters for world elites in the event of an apocalypse.

Another line of speculation focuses on secret societies. Some claim that the airport was built with connections to Freemasonry, the Illuminati or the so-called New World Order. A plaque placed at the airport’s dedication mentions a ‘New World Airport Commission‘, which has been interpreted by some as a hidden message. The date of the dedication and certain symbols carved into stone have also been linked, often tenuously, to Masonic lore.

The airport’s art has inspired further theories. The ‘Blue Mustang’ statue with glowing red eyes is sometimes seen as an omen of death, especially as the sculptor was tragically killed when part of the statue fell on him. 

Murals by artist Leo Tanguma, which depict scenes of war, destruction and peace, have been read by conspiracy enthusiasts as prophecies or coded messages about global catastrophe and rebirth. Gargoyle statues and other decorative features have also been swept into these interpretations.

Even the runways are not immune to speculation. From above, some observers claim that their layout resembles a swastika, though this is disputed and largely a matter of interpretation.

What is unusual is the way the airport itself has responded. Rather than ignoring the stories, it has leaned into them with a sense of humour. 

Construction walls have featured posters joking about “remodelling the lizard people’s lair”, and the airport has even hosted exhibitions exploring its own conspiratorial reputation. Animatronic gargoyles and themed displays playfully acknowledge the myths while engaging visitors.

The persistence of these theories lies in the airport’s unique combination of scale, design and symbolism. Its vast and somewhat isolated location, striking architecture, mysterious underground spaces and provocative artwork create a sense of mystery that invites speculation. 

By embracing rather than rejecting this reputation, Denver International Airport has ensured that the myths remain as much a part of its identity as its runways and terminals.

Using Denver International Airport

Arriving at Denver International Airport, I was only greeted by friendly people. The U.S. Customs and Border Protection said nothing. Literally nothing. No questions asked. Odd. I guess my passport is self-explanatory and all the information needed is in the system.

I did walk many steps getting out. 

The airport is connected to Denver by the Regional Transport District (RTD Denver) A Line.  All very smooth and easy.

Flying out, I did walk the terminals, but I the lure of the lounge was too big. Oscar assures me there are plenty of food options. He loves “DIA”, as he calls Denver International Airport. 

Colorado 2025

1. REVIEW | Lufthansa Airbus A380 in business class from Munich to Denver, return.
2. DENVER | RiNo Art District – Coors Field – Lower Downtown – Union Station.
3. REVIEW | Catbird Hotel in Denver’s RiNo Art District.
4. REVIEW | Forney Transportation Museum in Denver.
5. DENVER | 16th Street Mall.
6. COLORADO | Boulder ft. Chautauqua Trail, Boulder-Dushanbe Teahouse and Pearl Street Mall.
7. DENVER | Visit of the Colorado State Capitol.
8. COLORADO | Denver Art Museum.
9. DENVER | History Colorado Center.
10. UNITED STATES | Introducing Denver in Colorado.
11. REVIEW | United Club B Gates East & United Club A Gates West business class lounges at Denver International Airport.