My New Year's Eve Among the Mummies by Grant Allen

J. Arbuthnot Wilson (pseudonym of the real author, Grant Allen) tells this short story of his strange night spent inside "the great unopened Pyramid of Abu Yilla" in Egypt. On New Year's Eve, on the night before his group was to take a guided tour and climb the still sealed pyramid, he set out on his own to walk around the pyramid to relieve his boredom. He happened to find the secret entrance stone, which he pushed open. What he experienced deep inside the pyramid was a once-in-a-thousand-years event.

"Never as long as I live shall I forget the ecstasy of terror, astonishment, and blank dismay which seized upon me when I stepped into that seemingly enchanted chamber. ... I gazed fixedly at the strange picture before me, taking in all its details in a confused way, yet quite incapable of understanding or realizing any part of its true import."