Yellowstone stretches across parts of Wyoming, Montana, and Idaho, and this film moves through its geothermal basins, forests, and river canyons season by season. It traces the park's founding in 1872, when Congress and President Ulysses S. Grant created the world's first national park, and follows the shift in management to the newly formed National Park Service in 1917. Old Faithful erupts on schedule as the film's centerpiece, but the survey extends to the boiling springs and mud pots that make up roughly half the planet's geothermal features, all sitting atop the Yellowstone Caldera beneath Yellowstone Lake. The film covers Theodore Roosevelt's connection to the park's bears and conservation legacy, and tracks wildlife including elk herds, bison, and wolves, reintroduced after near-extinction and now established across the landscape. Native American communities' long presence in the region gets acknowledged as part of the park's history rather than treated as a footnote. The film reads as a straightforward tour of the park's natural features and the decisions that turned it into protected land.