In 1897, the United States was mired in the worst economic depression that the country had yet endured. So when all the newspapers announced gold was to be found in wildly enriching quantities in the Klondike River region of the Yukon, a mob of economically desperate Americans swarmed north. Within weeks tens of thousands of them were embarking from western ports to throw themselves at some of the harshest terrain on the planet -- in winter yet -- woefully unprepared, with no experience at all in mining or mountaineering. It was a mass delusion that quickly proved deadly: avalanches, shipwrecks, starvation, murder.