ROME'S BURIED SECRETS http://www.sciencechannel.com/ The Pantheon in Rome, Italy, was completed by emperor Hadrian around 126 AD. The dome alone weighs 4,535 metric tons. Watch full episodes: http://www.sciencechannelgo.com Subscribe to Science Channel: http://bit.ly/SubscribeScience Check out SCI2 for infinitely awesome science videos. Every day. http://bit.ly/SCI2YT