Who built the pyramides?

One of the most popular theories outside the scientific community is the one that talks about the construction of the Egyptian pyramids. Some people thinks that aliens may have participated directly or indirectly in their construction. 

Proponents of this idea argue that it is hard to believe that, with the simple tools and technology available more than 4,500 years ago the Egyptians could have cut, transported, and fitted together millions of stone blocks, some weighing several tons, with such precision. 

They argue that the Great Pyramid of Giza is aligned with surprising accuracy with respect to the cardinal points and that its layout reflects the constellation of Orion, which they interpret as advanced astronomical knowledge transmitted by visitors from other worlds. 

Adding to this myth is the belief in the intervention of giants or of enormous size creatures mentioned in ancient texts and traditions from different cultures, who would have possessed the necessary strength to move the enormous stone blocks and collaborate with humans under the guidance of the "gods from the stars"

 Although traditional archaeology explains their construction through human ingenuity, the use of ramps, and the organization of thousands of workers, these alternative theories have endured nowadays.