Ancient South Arabia: From the Queen of Sheba to the Advent of Islam - Klaus Schippmann - Google Books

http://books.google.de/books?id=L0K63L93cPcC&pg=PA7

At a crossroads between Africa, Asia, and Europe, the South Arabian kingdoms were major commercial and cultural players in world history. Their art and architecture, and especially their irrigation system, featuring a gigantic dam high in the mountains,…