Denver International Airport (DEN) is an airport in Denver, Colorado, United States. At 33,531 acres (52.4 sq mi), it is the largest airport in the United States by total land area. Runway 16R/34L, with a length of 16,000 feet (4,877 m), is the longest public use runway in the United States. As of 2016, DEN was the 18th busiest airport in the world and the sixth busiest in the United States by passenger traffic with over 58 million passengers. It also has the third largest domestic connection network in the country. As of August 2017, the airport features 135 gates spread out over three detached, yet internally connected, linear concourses (A, B & C).
DEN has non-stop service to destinations throughout North America, Latin America, Europe, and Asia serving 187 destinations in 2015. The airport is in northeastern Denver and is owned and operated by the City & County of Denver Department of Aviation. DEN was voted as the "Best Airport in North America" by readers of Business Traveler Magazine for six years in a row (2005–2010) and was named "America's Best Run Airport" by Time Magazine in 2002.
As of 2017, Denver International Airport has been rated by Skytrax as the 28th "Best Airport in the World," falling to second place in the United States behind only Cincinnati/Northern Kentucky International Airport. Skytrax also named DIA as the second "Best Regional Airport in North America" for 2017, and the fourth "Best Regional Airport in the World."
The airport is the main hub for Frontier Airlines and Great Lakes Airlines. It is also the fourth-largest hub for United Airlines with 375 daily departures to 141 destinations. The airport is Southwest Airlines' fourth most utilized airport and fastest-growing market, with 190 daily departures to nearly 60 destinations.
DEN is the only airport in the United States to have implemented an ISO 14001-certified environmental management system covering the entire airport.
The airport is accessible via Peña Boulevard as well as the A Line commuter rail from Denver Union Station.