Egypt, however, is also flat enough in most places that they could have an airstrip in the remote location.  The Egyptian interrogation sites normally mentioned in news articles are known Egyptian intelligence facilities right in Cairo, but in those places the detainees would be in the custody of Egyptian authorities, not the CIA.  There are rumors and speculations about where a black prison might be located here, but no hard evidence that I'm aware of.

A few articles have metioned Libya as a possibility as well, but I also find that unlikely, although not for the reasons you'd probably expect.

And the US public seems to be largely unaware of it, which is even more troubling.