Our Pick
Posted on @rawstates
Aerojet in the foothills
1951
Rancho Cordova, California
Rocket motors were tested on 20,000 acres east of the city, engines for Titan, Apollo's service module and the Space Shuttle's orbital thrusters. The firings could be heard across the valley, and the site is now one of the largest groundwater cleanups in the country.
That was 1 of the hidden places.
Location: historic site
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