John Muir first saw Alaska in 1879, only twelve years after it was purchased from Russia by the United States. Four more times, in 1880, 1881, 1890, and 1899, he was drawn back to this land of rivers and glaciers, sunsets and northern lights, campfires and Arctic stars. Few people have lived so many adventures, yet Muir was not a mere collector of adventure; the hazards he encountered - and many were spine-tingling - came as a result of his intense desire to examine new aspects of the natural world.