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"The purpose of this book is to insure a deep appreciation of the eight-valley region in southern Arizona and to raise awareness of the various watershed organizations taking action to improve the land and humankind's relationship to it."--Preface. The eight valleys are the Altar Valley, the Upper Santa Cruz Valley, the Cienega Valley, the San Rafael Valley, the San Pedro Valley, the Sulphur Springs Valley, the San Simon Valley, and the San Bernardino Valley.