The park contains the Yellowstone Caldera, which measures approximately 30 by 45 miles.
Thermophilic bacteria living in the hot springs produce the vibrant colors visible in Grand Prismatic Spring.
The park was the first officially designated national park in the world, established in 1872.
Obsidian Cliff is a site where prehistoric people sourced volcanic glass for tools and trade.
The park's altitude ranges from approximately 5,282 feet to 11,358 feet at Eagle Peak.
Approximately 1,000 to 3,000 earthquakes occur within the park boundaries annually.
The park features over 500 active geysers, the highest density on the planet.
Old Faithful erupts roughly every 90 minutes, though intervals can vary between 60 and 110 minutes.
The Yellowstone River is the longest un-dammed river in the contiguous United States.
Bison are the only animals in the United States to have lived continuously in the wild since prehistoric times.
Yellowstone National Park spans 2.2 million acres across Wyoming, Montana, and Idaho, sitting primarily atop a dormant supervolcano. It contains roughly half of the world's active geysers, including the predictable Old Faithful. The park is home to the largest concentration of mammals in the lower 48 states, including grizzly bears, gray wolves, and the largest public-herd of bison. The Grand Canyon of the Yellowstone, carved by the Yellowstone River, features two major waterfalls, the Lower Falls dropping 308 feet. Mammoth Hot Springs displays travertine terraces created by geothermal water depositing calcium carbonate. Hayden Valley and Lamar Valley serve as prime locations for wildlife observation due to their expansive meadows. The park landscape is shaped by rhyolite lava flows and post-glacial volcanic activity. It maintains significant hydrothermal features, including mud pots, fumaroles, and prismatic hot springs colored by thermophilic bacteria.
The overlook trail for the Grand Prismatic Spring provides the best vantage point of the entire multicolored pool.
Carry EPA-approved bear spray and know how to use it when hiking in backcountry areas.
Stay on designated boardwalks around geothermal features to avoid thin crusts and boiling water.
Use binoculars or spotting scopes for wildlife viewing to maintain a safe distance of at least 100 yards from bears and wolves.
Download offline maps before arrival, as cellular service is extremely limited or non-existent in the park.
Attempting to drive across the entire park in a single day, as traffic congestion and slow-moving wildlife often cause significant delays.
Most park roads close to private vehicles in early winter and reopen in late spring; specific opening dates depend on snow clearance progress.
Maintain at least 25 yards distance from bison and elk, and 100 yards from bears and wolves; do not feed wildlife; stay on marked paths.
