The popular greeting or response of a thumbs up actually originates from the Colosseum.
It was a signal that the gladiator was to be put to death via the jugular! Dead gladiators were carried out of the west exit, which came to be known as the Gate of Death.
There are certainly way too many to see in one visit. So to help those who will soon be vacationing in the States, here are the top tourist attractions...
