i did a search on site 4. . .

Site 4: More Secret Than Groom Lake?
Site Four is located within the boundaries of TTR, near the eastern border, about 10 miles east and slightly south of the TTR headquarters. Access to Site Four is provided not only from within TTR, but also from a gate on TTR's eastern boundary. From this "Site Four Gate", as it is called, a high quality dirt road (similar to Groom Lake Road) heads east and connects with Hwy. 375.

Site Four sits by itself on a large plain. It is easily observed from a number of locations, although from a distance. It is a large complex, spread over several miles, with some of the buildings widely separated. It is also worth noting that while TTR is covered with an assortment of camera and radar tracking facilities, there is a notable absence of these near Site Four, adding to its appearance of isolation.

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