let me explain, through various archeological studies and so on regarding the pyramids etc. someone was suveying the underground area with ultrasound scanners and so on. they made a discovery of a chamber under the sphynx at the front. now because the sphynx pre-dates the egyptians due to the dating of the erosion on it, it was built when the area was lush (the pharoes re-carves the head from a lion to a man), the civilisation then was theorised to be part of that of atlantis as some believe its in the med not the atlantic. long story short, hyrogliphs, carbon dating and myths lead some archeologist to believe that the chamber is actually the fabled library of atlantis. but the egyptian government has never, and will not allow anyone to open this chamber.