In Douglas Adams' The Hitchhiker's Guide to the Galaxy, 42 is the number from which all meaning ("the meaning of life, the universe, and everything") can be derived. It is also a subroutine programming code when initiated closes the main program. Since a person is choosing exit 42 on I-75 it also means you are leaving the main program > I-75
It's in the middle of Lake Superior, Michigan, 24 miles from shore, and maintenance crews would have to hack ice off from the door to reach the keepers. It's the Stannard Rock Lighthouse, the loneliest place in North America.