Editing Safeguard Program (section)

===Perimeter Acquisition Radar (PAR)===
[[Image:Cavalierairforcestationparcs.jpg|thumb|right|The PAR, known now as PARCS (for Perimeter Acquisition Radar Cueing System) is still operational]]

The PAR was a large [[passive electronically scanned array]] radar that was intended to detect incoming ballistic missile warheads as they crossed over the North Pole region.  Potential targets detected by the PAR would be sent to the Missile Site Radar (MSR) and to [[North American Aerospace Defense Command]].  Two radar sites were intended to be constructed on the northern border of the United States, one in Montana and one in North Dakota.  Construction was begun at both locations, but because of the ratification of the [[Anti-Ballistic Missile Treaty]], only the site at North Dakota was completed.  That site, near [[Cavalier, North Dakota]], is now operated by the [[United States Space Force]] as [[Cavalier Space Force Station]].<ref>[https://www.buckley.spaceforce.mil/News/Article-Display/Article/2715043/cavalier-afs-renamed-as-us-space-force-installation/ Cavalier AFS renamed as U.S. Space Force installation]</ref>

Remnants of the Montana PAR site are located east of [[Conrad, Montana]], at {{coord|48|17|15.83|N|111|20|32.39|W|type:landmark}}.