Denver International Airport Automated Guideway Transit System Denver International Airport Automated Guideway Transit System The Denver International Airport Automated Guideway Transit System is a people mover system operating at Denver International Airport in Denver, Colorado. The system opened along with the airport itself in 1995, and was conceived as a means to connect all of the midfield concourses with the south terminal and quickly transport passengers between them because of the longer distances between each building, especially when compared to Stapleton International Airport, Denver's former airport. Located within the secure areas of the airport, the AGTS utilizes two mile-long tunnels traveling underneath the aircraft taxiways and passing
Denver International Airport away than Stapleton International Airport, the airport it replaced. The distant location was chosen to avoid aircraft noise affecting developed areas, to accommodate a generous runway layout that would not be compromised by blizzards, and to allow for future expansion. The 52.4 square miles (136 km) of land occupied by the airport is more than one and a half times the size of Manhattan (33.6 sq mi or 87 km2). At 33,531 acres (136 km), DIA is by far the largest land area commercial airport in the United States. Dallas/Fort Worth International Airport is a distant second at 70 km