All through history, availability of salt has been pivotal to civilization. In Britain, the suffix "-wich" in a place name sometimes means it was once a source of salt, as in Northwich and Droitwich, although other - wich towns are so named from the Saxon 'wic', meaning fortified dwelling or emporium. The Natron Valley was a key region that supported the Egyptian Empire to its north, because it supplied it with a kind of salt that came to be called by its name, natron. Today, salt is almost universally accessible, relatively cheap, and often iodized.