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THE L-4 COAXIAL SYSTEM
(How the Bell System helped win the cold war)
by Mark Foster ( [email protected])

Bell Routes circa 1980

This site is dedicated to the L-4 coaxial system. The L-4 system was developed to support defense related communications during the cold war period (See related discussion of the Air Force'sWinter Study Report ) . The L-4 system was "hardened" meaning that it was designed to withstand a nuclear attack. While this site refers to the L-4 system it also includes L-3 systems the predecessor to the L-4 system. Some texts just refer to the entire system as the "L" system. The system was also referred to "The Transcontinental Cable System". The "L" system consisted of over 100 "Main Stations" and 1000 repeater vaults, each one designed to withstand a nuclear environment. Main stations also were designed complete with generators, blast doors and housing for employees for the 2 week period that followed Armageddon. This system provided hard wire communications paths for almost all of the key command and control facilities in the continental United States. Major cold war events such as the Cuban Missile crisis were carried over the L system. Most of the system was dismantled in the late 1970's and early 1980's as the need for a ground based command and control system evaporated. The final blow occured when the Bell System was broken up and ability to pass the operating costs along to the consumers vanished. Much of the current command and control communications requirements are now provided by hardened satellites, and fiber. This site is dedicated to the personnel (sometimes referred to as moles) who toiled underground during the cold war to provide this critical service.

HARDENED SITE UNDER CONSTRUCTION CIRCA 1966