Denver International Airport, or DEN (though it’s often referred to as DIA as well), is located in Denver, Colorado. It’s the largest airport in the U.S. by land area, at 52.4 square miles: more than one and a half times bigger than the island of Manhattan. The sixth busiest by passenger volume, it served more than 54 million travelers in 2015. DEN replaced Stapleton International Airport, which was established in 1929 and was 19 miles closer to downtown Denver, as the city’s airport in 1995. Stapleton has since been decommissioned.With its circus-tent like roof, Jeppsesen Terminal (honoring aviation safety pioneer Elrey Jeppesen) is instantly recognizable, with peaks recalling the nearby Rocky Mountains. The complex fabric-covered roof—actually Teflon-coated fiberglass—is supported by a system of steel cables not unlike those holding up the Brooklyn Bridge.Denver International Airport is, puzzlingly, the subject of many conspiracy theories. One has it that the airport’s runways are laid out to mimic a swastika. Several are concerned with the artwork used to decorate the airport, in particular two murals by Leo Tanguma, “Children of the World Dream of Peace” and “In Peace and Harmony with Nature,” located near baggage claim. (Perhaps it’s this often-frustrating place that leads travelers to turn their thoughts to invisible, malign machinations.) Both considered diptychs, each work is made up of one smaller panel that depicts a dystopian scene and a much larger panel that depicts a utopian landscape. Some people believe the murals predict the end of the world. “Blucifer,” a giant cerulean horse with glowing red eyes (its official name is “Blue Mustang”), can’t help matters either. Its sculptor died when a 9,000-pound section of the statue fell on him.The A Line commuter rail links the airport to Denver Union Station. Peña Boulevard provides road access.