According to the AP:
The closure follows a string of unconfirmed reports in local media that unidentified groups would try to hold "Jewish" or "Masonic" rites on the site to take advantage of mysterious powers coming from the pyramid on the rare date.
Egypt's Ahram Online reported that a meditation ceremony had been scheduled to take place at the foot of the Great Pyramid. Called the "ceremony of love," it was intended "to save the earth from cosmic threats."
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There were also rumors that 1,200 Jews wanted to put a Star of David atop the pyramid, according to the Jerusalem Post.
The rest of the Great Pyramids complex, which includes two other smaller pyramids, several tombs and the Sphinx, remained open to visitors. The 450-feet-high Great Pyramid of Giza is one of the seven wonders of the ancient world.
The Great Pyramid houses the tomb of Pharaoh Cheops, also known as Khufu, who ruled Egypt from 2589 to 2566 BC.
Agence France-Presse quoted a Department of Pharaonic Archeology official as saying that the decision to close the Great Pyramid came "after much pressure" from Egyptian Internet users, who had said that rituals would be held "within the walls of the pyramid on November 11, 2011."
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