Source: National Geographic - Premiered December 12, 2010 (used without permission):

Rome was the largest empire, the mightiest military force and the most advanced civilization on earth, but most of all, it was a place - a city. Though only traces remain, and most of its ruins lie buried beneath modern streets. Written here, in stone, is the story of the ancient Romans. Using new finds and new thinking the fragments are being pieced back together. These people took a swamp and drained it. They perfected concrete the most versatile construction material on earth, quarried thousands of tons marble and used it all to build the imperial capital. Centuries of innovation, endurance and ambition. This is the story of the greatest city on earth.

(Advanced appreciation is rendered for materials used without express permission of copyright owners – Tommy Peters)