Stapleton International Airport Stapleton International Airport Stapleton International Airport was the primary airport serving Denver, Colorado, United States from 1929 to 1995. At different times it served as a hub for Continental Airlines, the original Frontier Airlines, People Express, Trans World Airlines (TWA), United Airlines and Western Airlines. Other airlines with smaller hub operations at Stapleton included Aspen Airways, the current version of Frontier Airlines and Rocky Mountain Airways, with all three of these air carriers being based in Denver at the time. In 1995, Stapleton was replaced by Denver International Airport. It has since been decommissioned and the property redeveloped as a
Stapleton International Airport officially opened for all operations the following morning. When it closed in 1995, Stapleton had six runways (2 sets of 3 parallel runways) and five terminal concourses. The runways at Stapleton were then marked with large yellow "X"s, which indicated it was no longer legal or safe for any aircraft to land there. The IATA and ICAO airport codes of DEN and KDEN were then transferred to the new DIA, to coincide with the same changes in airline and ATC computers, to ensure that flights to Denver would land at the new DIA. While Denver International was being constructed, planners