Secrets of Lost Empires: Reconstructing the Glories of Ages Past

How were the great civilizations of the past able to build Stonehenge, the Pyramids, Egyptian obelisks, the Colosseum, and the Inca monuments without modern technology?

Recruiting engineers, architects, archaeologists, stonemasons and other assorted craftsmen, Nova and the BBC attempt to answer this question as they set about to recreate these five wonders of ages past.