Overview
Yellowstone National Park was established by the U.S. Congress and signed into law in 1872 to protect a spectacular landscape of mountains, rivers and thermal features. Located primarily in the U.S. states of Wyoming, Montana and Idaho, the park takes its name from the Yellowstone River that drains much of the area. It was designated a UNESCO World Heritage site in 1978 in recognition of its global geological and ecological significance. For more background see the park's general information pages: park overview and national context: United States.
Geology and geothermal features
Yellowstone sits atop a large volcanic caldera created by repeated eruptions over millions of years. The heat below the surface fuels an extraordinary array of geothermal phenomena — geysers, hot springs, fumaroles and mud pots — that draw scientists and visitors alike. The park contains roughly half of the world’s geysers, including the famous Old Faithful. Many resources describe these features and ongoing research into their origins: geysers and hot springs.
History of protection and management
Yellowstone’s creation marked a major shift in how natural places were valued and protected. President Ulysses S. Grant signed the establishing act, and subsequent laws and management practices have evolved to balance preservation with public access. The early legislation and continuing conservation measures are discussed in historical summaries: founding law.
Wildlife and the Greater Yellowstone Ecosystem
Beyond its geology, Yellowstone is famed for large mammals and diverse habitats. Grizzly bears, wolves, bison and elk are some of the most visible species. Management and recovery programs have focused on key species such as the reintroduced wolves and the park’s iconic bison. The park sits at the core of the Greater Yellowstone Ecosystem, widely regarded as one of the largest nearly intact temperate-zone ecosystems on Earth (intact ecosystem), containing extensive subalpine forests and other plant communities including the subalpine forest zone.
Visiting, uses and notable facts
Yellowstone receives millions of visitors annually who come to view geothermal features, wildlife and landscapes. Visitor infrastructure, education programs and seasonal access rules aim to reduce human-wildlife conflicts and protect fragile thermal areas. Practical guidance and official resources are available for planning visits: visitor information, safety briefings: travel context, and interpretive materials: historical resources.
Distinctive features and challenges
Key distinctions that set Yellowstone apart include:
- Its status as the world’s first national park and an early model for global conservation.
- A concentration of geothermal activity unmatched by most protected areas.
- Its role as the ecological core of a vast, connected landscape that supports large-ranging species.