Atlantis: The Mother of Time by J. Robin E. Harger
Approx. 50,590 words.
Published on July 10, 2012.
The Great Pyramid was decommissioned through misadventure by Atlantis but it was built and encoded prior thereto by visitors as part of an undertaking that had driven them across the vast reaches of space. Reforming the stumbling proto-humans they had long-since departed leaving us to take up our own destiny in the mighty task of spreading human consciousness throughout the universe.