[JoeProBono]

Air Force tunnel boring machine links deep underground military bases across U.S.

[grey_whiskers]

It *is* pretty d@mn boring, isn't it?

Cheers!

[Portcall24]

I think this was probably the machine which dug the tunnels to link the control module to the ICBMs in the Western U.S. I visited one of those sites in Idaho in 1966 just after it had been deactivated because of a treaty.