Pyramid: The Last Secret Timewatch : Season 19 Episode 6

The story of an architect's obsession with the grand pyramid if Gizeh, built for Pharoah Chefu, helped by high-tech 3D model-programs and various experts. A new, more plausible theory of how the pyramids were built is discussed, using not just an external ramp but also an ingenious system based on a winding, sloping internal ramp and counterweight trolleys, to pull up granite beams. Testing it on site lead to more discoveries.