Ancient Egyptian obelisks are tapering stone pillars which have a square cross-section, and which are believed to have had religious, socio-political and ornamental functions. Some weigh more than 400 tons.They appear to have been 'carved' from solid granite using a method which leaves characteristic and regular 'scallop' marks on their surface.

Although many of the quarry sites have been found to feature round stone tools made from dolerite (harder than granite) "[…] no scientific explanation of these scalloped cut marks has ever been published."

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Also see: The Pyramids - constructionplugin-autotooltip__plain plugin-autotooltip_bigThe Pyramids - construction

Construction engineers and archaeologists have not been able to agree on the ways in which the Great Pyramids of Giza (and others) might have been constructed - at around 2580–2560 BC.

"The logistics involved in the construction of this pyramid are staggering when one considers that the ancient Egyptians had no pulleys, no wheels, and no iron tools.