Anyone who knows even a bit about Roman history would almost certainly know of the Colosseum, the great arena in Rome. Made from marble and granite, the Colosseum would hold thousands of people, whether they were watching a comedy, or whether they watched fearsome gladiators fight each other to the death. After violent episodes of men brutally slaying each other, the Colosseum would reek of blood and gore, but this wouldn't diminish the wonder of such a building. It was 48.5 meters (158 feet) tall and its ellipse-like shaped measured 188 by 156 meters (615 by 510 feet). The Colosseum contained columns in Doric, Ionic, and Corinthian styles. Its floor was made of oaken planks covered with waterproof cloth (for mock sea battles) and sand. However, literally under this floor were the obscure tunnels of the Colosseum. These were made from concrete and stone, and were amazing examples of unseen architecture. Anonymous these tunnels were; they were meant to be functional, not glorious. The Colosseum's passages were built to provide the performers better access to the arena. Trapdoors and hand-powered elevators were used to create a dramatic effect wherein the performers would rise from the floor, seemingly forming from the sand. The performers waited in small rooms until it was almost time to perform. They would then walk along the many passages before making a grand entrance onstage. Entrances of boats into the Colosseum were more complex. A system of locks and gates rose the boats up into rooms hidden beneath the area where the visitors sat, and boats were sailed through gates into the vast artificial lake. Inside the dark passages, curious graffiti in both Greek and Latin was found on the walls, as well as murals done by the inhabitants. In fact, an old passageway out of use led to a room outside the Colosseum which may have been a hideout for criminals, who were abundant on the streets of Rome. The tunnels in modern cities also lurk underground, the shy cousins of bridges and bypasses, but many of these tunnels, such as subways, are quite populous. In the case of the British Thames tunnel (which is still part of the London Underground after over a hundred years), the Parliament had restrained from building a second bridge instead because a bridge would be too much of an inconvenience for river traffic. Perhaps in The Hitchhiker's Guide To The Galaxy, by Douglas Adams, the aliens should have built a tunnel instead of demolishing Earth to build a bypass... then again, maybe not.
Sources:
http://www.destination360.com/europe/italy/colosseum.php (Picture credit)
