The Oldest Building on Earth

The Tim Traveler is looking for the oldest surviving building on earth. Now, you notice that there is no building identified in the title of this post, because such a question will have a lot of qualifiers. First, you have to define what you mean by "building," and then you have to define what you mean by "surviving." There could be any number of old buildings to top the list, depending on how you define those terms. Which is good, because that means we get to learn about several very old structures in this video. Tim has qualifiers that are different from Wikipedia's list. He makes the argument for the Cairn of Barnenez in France, because you can still go inside it and have a roof over your head. That would make me a bit nervous, because I've had bad experiences with very old man-made roofs. -via Digg