I know a guy who built a tunnel from his castle to his race track and salvage yard. I hope when he dies they turn the castle he made into a museum. He built it also.
That was crazy. It got crazier as it went along when he said now I'm going to the front of the house, then at the end he shows his plans for an underground garage and lift...wow!
It is similar to watching Clarkson's farm where to get anything done in England you have to either beg for permission or hide it. Asking first always results in a "no".