Exploring the great wilderness of Alaska's Brooks Range was Robert Marshall's joy and delight during the decade between 1929 and 1939. Marshall traveled this spectacular country, from the Upper Koyukuk drainage to the Arctic Divide, making maps, recording scientific data, and exalting in the beauty of that incredibly pristine landscape. Although his early death at thirty-eight ended an exceptional life too early, he left journals and letters to describe his favorite place on earth. These were edited by his brother George Marshall and were compiled to create this classic of environmental literature, now in its third edition after nearly fifty years in print and with a new foreword by Rick Bass.