Rome Colosseum: Italy unveils plan for new floor with gladiator’s view

I watched a documentary on the Colosseum and it was fascinating. It could hold up to 80,000 people. The Romans were concerned about the flow of traffic and how to change the "floor plans" quickly. Modern stadium designers use the same principles that were incorporated in the building of the Colosseum. At a glance one would see the external structure, but it was an engineering marvel underneath.