H.A.R.P.- Yuma Testing Grounds. Sept 11, 2020 20:58:58 GMT Quote Select PostDeselect PostLink to PostBack to Top Post by larryc1 on Sept 11, 2020 20:58:58 GMT This is an intact supergun. It fired projectiles into the ionosphere between 1966 and 1969. It was used for other tests as late as 1992. Shorter barrels are just to the north of the gun. kjzz.org/content/359404/how-giant-space-gun-ended-middle-arizona-desertH.A.R.P.- Yuma Testing Grounds..kmz (1018 B)