Take a deep dive into the history of our country's national parks—from the first sparks of the idea of land preservation, to the founding of Yellowstone, to the most recent additions to the ever-growing national parks system. Duncan and Burns dig into the importance of figures like Theodore Roosevelt and Ansel Adams, into the details and intricacies of particular parks, and into the beliefs and ethics that have helped the system flourish into a network of nearly 400 sites.