In 1870, Truman Everts visited what would two years later become Yellowstone National Park, travelling with an exploration party intent on mapping and investigating the region. In "Thirty-seven Days of Peril” he recounted his experiences. In 1996, Everts's granddaughter discovered a brief autobiography that gave new insight into his early life, and a never-published alternative account of his 1870 journey. Both have been added to this volume.