Operation Gold

Operation Gold was a joint operation conducted by the American Central Intelligence Agency and the British MI6 Secret Intelligence Service in the 1950s to tap into landline communication of the Soviet Army headquarters in Berlin using a tunnel into the Soviet-occupied zone. This was a much more complex variation of the earlier Operation Silver project in Vienna. Soviet authorities were informed about Operation Gold from the very beginning by their mole George Blake and "discovered" the tunnel in 1956.

Details of the project are still classified—especially by the British—and whatever authoritative information can be found is scant. This is primarily because the then-Director of Central Intelligence , Allen Dulles ordered "as little as possible" be "reduced to writing" when the project was authorized.

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