An airway beacon was a rotating light assembly mounted atop a tower. These were once used extensively in the United States for visual navigation by airplane pilots along a specified airway corridor. Approximately 1,500 airway beacons were constructed to guide pilots from city to city, covering 18,000 miles.
Airway beacons were constructed by the Post Office and the Department of Commerce between 1923 and 1933. The Low Frequency Radio Range system began to replace this visual system in 1929. The last visual airway beacon was supposedly shut down in 1973, but some airway beacons are still operating in Western Montana and are charted on the Great Fallssectional chart. They are maintained by the Montana Department of Transportation Aeronautics Division.
One beacon is preserved for historical purposes in Saint Paul, Minnesota at the Indian Mounds Park on a bluff overlooking the Mississippi River. Recently, the beacon at Grants, New Mexico was restored for historic preservation, using original items found at other nearby sites.
A large concrete slab, in the shape of an arrow, was located near the base of each beacon. Many of these arrows remain today, some of which are visible from satellite pictures, even in urban settings.