Nobody knows how the Great Pyramid was built: neither ramps nor wet sand can lift seventy-ton granite blocks three hundred feet into the air.

But that is not going to help you get dozens of 70 ton granite blocks 300 feet in the air to form the roof of the King’s Chamber and the floor of the chamber above it, and the roof of that chamber, and the floor of the chamber above that, and so on and so forth. Wet sand never got those objects up there.