Assyrian Warriors Attack a CityIn this Assyrian carving from a royal throne room made about 865 B.C.E., warriors cross a river on inflated skins, which both support them and provide air for breathing underwater. Such innovative techniques, combined with a large army and effective military organization, allowed the Assyrians to establish a large empire. (Werner Forman Archive/British Museum, London. Location: 10. © 2004 Werner Forman/TopFoto/The Image Works)