Yes, it is true that the Denver Airport has an underground city. The airport, officially known as Denver International Airport (DIA), is located in Denver, Colorado. The airport is famous for its unique and mysterious underground facilities.

One of the most well-known features of the underground city at DIA is the baggage handling system. The airport has an extensive network of tunnels and conveyor belts that transport luggage from the check-in counters to the aircraft. This underground system helps to streamline the baggage handling process and ensures efficient and timely delivery of luggage to the planes.

Additionally, there are also rumors and conspiracy theories surrounding the existence of secret underground facilities at the Denver Airport. These theories suggest that the underground city is much larger and more complex than what is publicly known. Some conspiracy theorists believe that the airport is a cover for a secret government base or even a secret society headquarters.

While these conspiracy theories lack concrete evidence, they have contributed to the mystique surrounding the Denver Airport's underground city. The airport authorities have embraced this intrigue and even incorporated elements of the conspiracy theories into the airport's artwork and design. For example, the famous "Blue Mustang" statue, also known as "Blucifer," which stands outside the airport, is said to symbolize the apocalyptic horseman of the conspiracy theories.

It is important to note that the airport authorities have denied the existence of any secret underground facilities beyond the publicly accessible areas. The underground city primarily serves practical purposes, such as housing the baggage handling system and utility infrastructure.

Overall, the Denver Airport does have an underground city, albeit on a smaller scale than some conspiracy theories suggest. The airport's unique underground facilities and the surrounding conspiracy theories have made it a topic of fascination and speculation for many.

References:

1. Denver International Airport - Facts
2. Atlas Obscura - Denver International Airport