in the Earth observations forum... or sort of, it must be noted that yesterday the NRO declassified the KH-7 and -8 GAMBIT and KH-9 HEXAGON high resolution photographic spy sats of the 60s, 70s and 80s.
here you can find some pics of the "rolling stock-sized" KH-9 http://www.spaceref.com/news/viewnews.html?id=1568
and on the NRO sites you can find hundreds of declassified documents http://www.nro.gov/foia/declass/GAMBHEX.html
unfortunately, all imagery from orbit seems to be redacted at this time