Coldwar Communications Centre - Images of the Past
owl writes:
https://coldwar-ct.com/Home_Page_S1DO.html
The Cheshire ATT facility is an underground complex originally built in 1966. It was an underground terminal and repeater station for the hardened analog L4 carrier cable (coax) that went from Miami to New England carrying general toll circuits and critical military communication circuits. It reportedly housed an AUTOVON 4-wire switch as part of the switching fabric of that critical global military communications network. Cheshire also connected via terrestrial microwave to the major, semi-hardened AT&T Durham station which linked to many other sites including paths to New London (Navy Sub base) and to Green Hill, RI to meet a transatlantic cable to Europe.
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