Underground Cities

I am frequently blown away by all that we don't know about our world. What's more surprising, though, is what we sometimes don't know about even the history of what we humans have built in this world. Often we've completely forgotten what the pinnacles of past societies were. Like in 1911 when Machu Picchu was rediscovered after being lost for centuries.

BLDGBLOG now points us to the underground cities of Cappadocia in Turkey. The ancient Hittites, who came to area from east of the Black Sea around 2,000 B.C., are believed to have begun the excavation of these cities. It is believed that these underground cities were enlarged during early Christian times to provide refuge for the Christians from invaders and persecutors.
He quotes Alan Weisman from The World Without Us,

No one knows how many underground cities lie beneath Cappadocia. Eight have been discovered, and many smaller villages, but there are doubtless more. The biggest, Derinkuyu, wasn't discovered until 1965, when a resident cleaning the back wall of his cave house broke through a wall and discovered behind it a room that he'd never seen, which led to still another, and another. Eventually, spelunking archeologists found a maze of connecting chambers that descended at least 18 stories and 280 feet beneath the surface, ample enough to hold 30,000 people – and much remains to be excavated. One tunnel, wide enough for three people walking abreast, connects to another underground town six miles away. Other passages suggest that at one time all of Cappadocia, above and below the ground, was linked by a hidden network. Many still use the tunnels of this ancient subway as cellar storerooms.

Did you catch that? Up to 30,000 people lived in this underground city!

And BLDGBLOG notes, it is likely there is more exploration of these cities waiting to happen. Another underground city, Gaziemir, was just found earlier this year.

What other crazy remnants of a past society are out there still waiting to be found again?