Fascinating article if you're a ufo geek like me-

Some of the greatest and most secretive airplanes in history have been developed in the Nevada desert, most of them at the now-infamous base known as Area 51. It turns out Area 51 has a sister facility -- Area 52 -- and it's a place with secrets of its own.

Area 52 isn't quite as secretive as Area 51. For one thing, you can at least find it on some maps. But it's off limits to most of us because of the classified work that goes on out there. The base has been bombed, blasted, poisoned, and nuked in the pursuit of cutting edge technology that probably can't be tested anywhere else.

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The base, all 525-square miles of it, is best known as the Tonopah Test Range, or TTR. In government documents, however, it's called Area 52, sort of a nod to a better known and far more secretive sister facility on the other side of the Nellis Range, Area 51. The connection between the two is more than sequential.

Joerg Arnu, Dreamland Resort webmaster, said, "Yes, TTR is really referred to in official documents as Area 52. On several occasions, black projects moved from Area 51 to TTR, Area 51 being, of course, a super-secret facility, TTR being slightly less secret. It's still a secret facility but not a supersecret facility."

More at the link.