"River of the Nation: A Report on the Potomac by the United States Department of the Interior" is a documentary book that explores the picturesque Potomac River that flowed through the capital of the United States of America - Washington. This report presents data and analysis on the condition of the river, its water resources, and the impact of human activities on the Potomac ecosystem. The authorship of this work belongs to the US Department of the Interior, which guarantees the objectivity and reliability of the information presented in the report. Thanks to this book, readers will have the opportunity to deepen their understanding of the importance of protecting natural resources and aquatic ecosystems for the preservation of the natural environment.