There are two airfields in Nevada that I can think of where it would be strongly advised to NOT land... But the airspace is all restricted anyhow, so one shouldn't be anywhere near there to begin with.

Back in happier times, I was tooling around in an F-15 near those airports, and was vectored onto a Mooney that was either lost or stupid, heading towards flying saucer world. Got near stall speed, scared the pants off the dude, and got him headed in the right direction.