It deals first and principally with the history of the Upper Yellowstone from the days of Lewis and Clark to the present time. The main text is supplemented by a considerable amount of appendical matter, the most important features of which are a complete list of the geographical names of the Park, with their origin and signification; a few biographical sketches of the early explorers; and a bibliography of the literature pertaining to this region. The descriptive portion of the work contains a succinct, though comprehensive, treatment of the various scientific and popular features of the Park. While it is sufficient for all the requirements of ordinary information, it purposely refrains from a minute discussion of those details which have been, or are now being, exhaustively treated by the scientific departments of the government. In describing a region whose fame rests upon its natural wonders, the assistance of the illustrative art has naturally been resorted to. The various accompanying maps have all been prepared especially for this work and are intended to set forth not only present geography but historical features as well. The folded map embodies every thing to date from the latest geographical surveys. It will bear careful study, and this has been greatly simplified by a system of marginal references to be used with the list of names in Appendix A. The illustrations cover every variety of subject in the Park and represent the best results of photographic work in that region. They are mostly from the studio of Mr. F. J. Haynes, of St. Paul, the well-known Park photographer, who has done so much by his art to disseminate a knowledge of the wonders of the Yellowstone. A considerable number are from views taken during the Hayden surveys by Mr. William H. Jackson, now of Denver, Colorado. A few excellent subjects are from the amateur work of Captain C. M. Gandy, Assistant Surgeon, U. S. A., who was stationed for some years on duty in the Park. The portraits are restricted to the few early explorers who visited the Upper Yellowstone prior to the creation of the Park. To any one who is familiar with the recent history of the Park, a work like the present would seem incomplete without some reference to those influences which endanger its future existence. A brief discussion of this subject is accordingly presented, which, without considering particular schemes, exposes the dangerous tendencies underlying them all. In the course of a somewhat extended correspondence connected with the preparation of this work, the author has become indebted for much information that could not be found in the existing literature of the Park. He desires in this place to return his sincere acknowledgments to all who have assisted him, and to refer in a special manner. To the Hon. N. P. Langford, of St. Paul, whose long acquaintance with the Upper Yellowstone country has made him an authority upon its history.