Denver Air Defense Sector The Denver was a NORAD geographic area designated during the Cold War in the Zone of Interior ( ZI ) for both air defense and air traffic control , as well as the name of the planned military unit for conducting radar surveillance and fighter - interceptor operations in the sector area . The Denver ADS spanned the entire state of Colorado , nearly all of Utah , most of Wyoming and western Nebraska , and small parts of Kansas , Oklahoma , New Mexico , Arizona , and Nevada . Targets in the sector included the military / industrial facilities and urban civilian populations of the metropolitan areas at Salt Lake City , Cheyenne , Denver , and Colorado Springs — the Colorado underground ICBM construction began in tbd . ( Omaha and Wichita military / industrial complexes were in the Sioux City sector ) . Along with the adjacent Reno Air Defense Sector , the Denver ADS was designated to be in the 27th Air Division ( " Rocky Mountain " division ) between August 1 and December 31 , 1958 , under NORAD ' s July 25 , 1958 , SAGE Geographic Reorganization Plan for the orderly transition and phasing from the manual to the " SAGE Defense System of radar stations , interceptor bases , and a new computer and communications network creating a Semi - Automatic Ground Environment . After 10 Super Combat Center ( SCC ) in underground bunkers were designated by the " USAF ADC Plan " approved by NORAD on December 20 , 1958 , additional Air Defense Command planning designated an SCC was to be constructed for command and control . The Denver SCC / DC was planned to become operational by May 1964 . Geography . The area of the Denver Air Defense Sector was an irregular pentagon from the Great Basin ' s northerneastern corner through the Central Rocky Mountains to the East border ( 100 . 65 meridian West ) in the Great Plains . Formed primarily from the southern portion of the pre - SAGE 29th Air Division , smaller additional areas of the 25th & 28th Air Division s were included to the West , the 25th & 34th ADs to the South , and to the East the 31st , 20th , & 33rd ADs . After the USAF had proposed Lowry AFB in 1958 for a new NORAD facility ( as it woould be temporary USAF Academy facilities were to be vacated ) , the bunker for both the sector headquarters and the SCC / DC at the Denver Metropolitan Area was published in the January – June 1959 NORAD Historical Summary ( declassified by NORAD / J3 in 1998 ) . Austere SAGE area . In June 1959 , in conjunction with SecDef approval for an " Improved SAGE environment " near coasts of the US and its Canadian border — plus 1 sector in Canada , an " Austere SAGE environment " was also planned . A military region in the " south - central and central area " of the US in 6 sectors defined in the July 1 , 1959 , SAGE Implementation Schedule : was constituted by NORAD on October 7 , 1959 , as the new " austere SAGE area " to have limited gap filler coverage and no advanced radars ) . Previously planned bunkers for the SCC / DCs at Denver ( 27th ) and San Antonio ( 33rd ) plus an above - ground AN / FSQ - 32 at Albuquerque were reconsidered for the austere SAGE area to instead have " three Super Combat Centers in soft configuration " . NORAD , USAF , and ADC agreed on a " new radar program " with the austere conditions , and on December 9 , 1959 , HQ USAF deferred construction of the underground " Denver " bunker for the SCC " because of budget considerations for FY 1961 " ( other SCCs , including the Ft Knox SCC / DC east of 86°30 ' , were approved despite the hold order on SCC equipment ) . Plans for the Rocky Mountain Division were discontinued by January 15 , 1960 , and coordination of interceptors for the general area was instead controlled by the 29th and 34th Air Divisions . The Denver SCC / DC was entirely cancelled with all Super Combat Centers on March 18 , 1960 , after a OSD evaulation and , at Ent Air Force Base in Colorado Springs was the only CONUS area not an Air Defense Sector .