Goetz uses five American valleys as illustrations--from the Shenandoah and the Tennessee to the anomalous, uninhabitable Valley of Ten Thousand Smokes--but her final page on ""valley homes,"" which lists climate and a sense of ""protection"" but not agriculture or access to transportation as reasons why people live in valleys, suggests how little purpose any of these particulars serve. Perhaps that's because the most salient points about valleys were already made in Rivers (1969).