One of the biggest mysteries about the Egyptian pyramids is the construction techniques used to erect them. The incredible feat of the Egyptians is all the more impressive when taking into consideration that over 2 million limestone and granite blocks were used to build the Great Pyramid of Giza.

The primary "mystery" surrounding the Egyptian pyramids, particularly the Great Pyramid of Giza, centers on how a Bronze Age civilization with no iron tools or pulleys moved and placed over 2.3 million stone blocks, some weighing up to 80 tons, with sub-millimeter precision. For centuries, theories have ranged from the use of massive external ramps to the "internal ramp" theory proposed by architect Jean-Pierre Houdin. More recent scientific "mysteries" include the discovery of the "Big Void" using muon tomography—a massive, previously unknown 30-meter-long chamber above the Grand Gallery whose purpose remains a subject of intense archaeological debate. There are also enduring questions about the astronomical alignment of the pyramids to the stars of Orion's Belt and the precision of the structure's orientation to true north. While fringe theories suggest "lost technologies" or extraterrestrial intervention, mainstream archaeologists point to a highly organized state labor force and sophisticated knowledge of geometry and hydraulics, as evidenced by the "Diary of Merer," an ancient papyrus logbook detailing the transport of limestone via the Nile.