Ghiglieri--ecologist, white-water guide, author of East of the Mountains of the Moon (1988)--provides a mile-by-mile tour of the wonders of the Grand Canyon and the Colorado River--a grab-bag of the sort of historical, geological, political, and anecdotal tidbits he apparently offers his white-watering guests, and a definitive source book for those who decide to take the challenge. Adrenaline Alley, Crystal Rapid, Soap Creek, Lava Canyon--the picturesque names of these spectacular Grand Canyon geological formations offer a hint as to why Ghiglieri claims to consider the Canyon his personal ""sacred ground."" Now an experienced guide who, when not pursuing scientific research projects in other parts of the world, takes boatloads of visitors down roller-coasterlike chutes, drops, and currents, Ghiglieri has settled down long enough to write the type of Grand Canyon guidebook that he claims he always wished he could find. Taking the reader along on an imaginary white-water journey, the author intersperses accounts of experiences he's had along the trail (hiking with flight attendants who insist on photographing one another naked on the cliffs; interrupting a tour to greet his first child, born in nearby Flagstaff and named, naturally, ""Cliff"") with passionate diatribes on the politics of water supply and its effect on the Colorado; evocations of the lives of the Anasazi Indians, whose centuries-old abandoned villages still dot the Canyon; and an insider's description of the cliffs, valleys, and hiking trails that line the river. Though Ghiglieri's enthusiasm and concern for the Canyon and its future are obvious throughout, his workmanlike prose may serve less to transport readers than to inspire potential adventurers to join him there.