Aliens and Ancient Engineers (S03E06)

Might the tools and technology of ancient builders have come from distant galaxies? Evidence suggests that an ancient mountaintop fortress in Peru was constructed with laser-like tools... temples at Vijayanagara India were built to harness cosmic energy... and an acoustic chamber in Malta enabled interplanetary communication. If the ancient builders did use advanced technology, could it prove that aliens visited Earth thousands of years ago? (iTunes)