This video is long, but contains alot of interesting info, and the lady who put it together with commentary is right on! At about 40 min. he is speaking about the travels of the ancient peoples in search of gold, jade, silver... Egyptians, Chinese etc. traveling before the time of Columbus "discovering" America. At about 50 min., they start getting into the Olnecs of S. America (Nephilim?) and various Nephilim skulls, including some of a supposed Cyclops. This is not a Christian interview, so the conclusions he draws fit more with the Ancient Aliens line of reasoning rather than a Biblical explanation (which the Bible clearly gives!).
Numbers 13:33 33 "There also we saw the Nephilim (the sons of Anak are part of the Nephilim); and we became like grasshoppers in our own sight, and so we were in their sight."