Book excerpt: Imagine driving 16,000 miles in 25 days over some of the roughest terrain in the world, at altitudes up to 16,000 feet, where engines and lungs gasp for air. Imagine 500-mile speed trials over rocky mountain tracks, racing against the clock and 95 other cars. Imagine attempting this more than 50 years ago, without GPS or cell phones or modern safety equipment. In April 1970, 241 men and women from more than 20 nations did just that, setting out from London in cars ranging from a dune buggy to family sedans to Porsches, Rolls-Royces, camper vans and a Jeep Wagoneer, determined to get to Mexico City. Drawing on personal recollections of competitors, organizers, marshals and mechanics, this book recounts the ecstasies and agonies of perhaps the toughest endurance motorsports event ever--the London to Mexico World Cup Rally.