More German Tunneling!!

[HOZ]

This time by the CIA during the cold war! Right from the horse's mouth

Fifty years ago, the CIA embarked on a project to intercept Soviet and East German messages transmitted via underground cable. Intelligence was collected to determine the best place to hit the target, and then concrete planning for a new collection site was begun.

The tunnel was 1,476 feet in length and consumed 125 tons of steel liner plate and 1,000 cubic yards of grout . . . This was not a small operation!

Early in 1951 when I was working in the Engineering Division of the Office of Communications, I received a message from some people in the office of the Deputy Director of Plans—specifically the chief of Foreign Intelligence/Staff D (FI/D), and a member of his team—requesting a meeting. [2]
The meeting was short. The only question they asked was whether a tunnel could be dug in secret. My reply was that one could dig a tunnel anywhere, but to build one in secret would depend on its size, take more time, and cost more money. After the meeting, I was transferred to FI/D. Thus began planning for the construction of the Berlin Tunnel.
We started building the tunnel in August 1954 and completed it in February 1955. It was 1,476 feet in length; 3,100 tons of soil were removed; 125 tons of steel liner plate and 1,000 cubic yards of grout were consumed. This was not a small operation!

[Reggie Dunlop]

Ja, zehr güt! Zey could lager ze beer in ze nice cold tunnel too. Very practical zoze Germans.