The world's first high-rise city?

I'd never heard of the city of Shibam, in Yemen, until I received a very interesting e-mail from Yusuf M. in Sana'a, that country's capital. I don't know how he learned of my blog, but he did, and sent me a series of very interesting pictures of Shibam. It looks like a fascinating place! (Click the pictures for a larger view.) According to Wikipedia: Shibam is a town in Hadramawt, Yemen with about 7,000 inhabitants. Shibam is thought to have already come into existence by the 2nd century AD…