Perimeter Acquisition Radar / PAR (Click photo for larger image)
The Mickelsen Safeguard complex was deployed during the 1970's to defend the offensive Minuteman missiles based at Grand Forks Air Force Base in the event of a nuclear ICBM attack by the Soviet Union or China. Depending on the threat, the system could also provide a limited defense of a wider geographical area, including other offensive Minuteman missile fields as well as civilian population centers. It was operational for approximately eight months.
The six sites that made up the complex are centered around the village of Nekoma, North Dakota, 100 miles northwest of Grand Forks.