"DEN has approximately 27 linear miles of land (roughly the width of the English Channel) along its fence line that is available for airport-compatible development," Day says. Thousands of additional acres beyond the perimeter will be ready for development during the next 50 years.

Within its boundaries, Denver International Airport constantly explores new opportunities to increase non-airline revenue through land development projects and is looking for the share of non-aeronautical revenue to increase against airline revenue so that airline operating costs can be reduced.

Currently, the hub derives funds from 76 oil and gas wells on airport property. Additional revenue is derived from dry wheat crops grown on vacant land.

The four-star, 500-room Denver Airport Hotel will soon be built next to DEN's Jeppesen Terminal, which will not only supplement non-aeronautical revenue but also give air travellers in Denver on-site accommodation and facilities for business conferences.

Another hotel (approximately 250 rooms) may be built on airport property on a 6.8 hectare tract of land called the Landings, which is parallel to DEN's entrance roadway; some retail may also be part of this development.

Cargo and logistics

The lack of airfield constraints and the absence of an operational curfew means cargo can be flown into and out of DEN at any time, day or night, while the airport's 16 hectare cargo ramp makes freight handling easy.

The airport's primary air cargo and mail facilities comprise five buildings on the airfield's south side. DEN's largest carrier, United Airlines, processes cargo in a 65,000sqft facility. Currently, 22% of DIA's air cargo is carried on passenger flights.

WorldPort, an airport area that that offers space for freight forwarders, customs brokers, and other related businesses, is nearby. A portion of this area is a Foreign Trade Zone.

Shipments ranging from perishables, such as meat, to precision instruments and telecommunications equipment make up the bulk of Denver's cargo freight.

With the second-largest aerospace economy in the United States, Colorado has more than 170,000 people employed in space-related jobs in as many as 300 companies. One of these companies, Lockheed Martin, ships rocket stages to Cape Canaveral from DEN.

The airport's enplaned air cargo accounted for about 45% of total cargo tonnage in 2009. Enplaned cargo tonnage increased an average of 4.2% per between 1995 and 2000, but has decreased each year since then for a number of reasons, including the US economic slowdown, which hit regional manufacturing particularly hard.

Cargo capacity in aircraft has declined at DEN as a result of more regional jets and because low-cost carriers, with smaller jets, have steadily grown their market share at DEN (now 43%).