Proposed evidence for ancient astronauts includes the existence of ancient monuments and megalithic ruins such as the Giza pyramids of Egypt, Machu Picchu in Peru, or Baalbek in Lebanon, the Moai of Easter Island and Stonehenge of England.
Supporters say that these stone structures could not have been built with the technical abilities and tools of the people of the time and further argue that many could not be duplicated even today.
They suggest that the large size of the building stones, the precision with which they were laid, and the distances many were transported leaves the question open as to who constructed these sites.

These ideas are categorically rejected by mainstream archeology.
Some mainstream archeologists have participated in experiments to move large megaliths.
These experiments have succeeded in moving megaliths up to at least 40 tons, and part have speculated that with a larger workforce larger megaliths could be towed with the use of known ancient technology.
Proposed evidence for ancient astronauts includes the existence of ancient monuments and megalithic ruins such as the Giza pyramids of Egypt, Machu Picchu in Peru, or Baalbek in Lebanon, the Moai of Easter Island and Stonehenge of England. Supporters say that these stone structures could not have been built with the technical abilities and tools of the people of the time and further argue that many could not be duplicated even today. They suggest that the large size of the building stones, the precision with which they were laid, and the distances many were transported leaves the question open as to who constructed these sites.
These ideas are categorically rejected by mainstream archeology. Some mainstream archeologists have participated in experiments to move large megaliths. These experiments have succeeded in moving megaliths up to at least 40 tons, and part have speculated that with a larger workforce larger megaliths could be towed with the use of known ancient technology.
Ancient astronauts