Egypt’s Pyramids of Giza were built to endure an eternity, but how remains one of the ancient world’s greatest mysteries.

Archeologists have long struggled to explain how the Egyptians got blocks weighing tons to the top of the 481-foot-high Great Pyramid, says Bob Brier in Archaeology.

A newly discovered ancient ramp at an Egyptian alabaster quarry could be the best clue yet as to how the pyramids were built.