Yellowstone National Park

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Yellowstone National Park is where the American national park idea was born — signed into law by President Ulysses S. Grant in 1872, it became the world's first national park and remains one of the most extraordinary places on Earth. Covering 2.2 million acres across the corner where Wyoming, Montana, and Idaho meet, Yellowstone sits atop one of the planet's largest active supervolcanoes, whose underground magma chamber fuels the most concentrated collection of hydrothermal features anywhere in the world. More than half of all the world's geysers — roughly 500 — are found here, including Old Faithful, which erupts approximately every 90 minutes and has done so reliably for centuries. The Grand Prismatic Spring, the park's largest hot spring, stretches 370 feet wide and glows in vivid rings of blue, green, yellow, and orange caused by heat-loving microorganisms called thermophiles — bacteria and archaea that are among the most ancient forms of life on Earth, and whose cousins likely first appeared in ancient seas billions of years ago. Beyond the geothermal drama, Yellowstone harbors America's largest bison herd (over 4,000 animals), grizzly bears, gray wolves (reintroduced in 1995 in one of conservation's great success stories), elk, moose, and pronghorn across a landscape that ranges from sagebrush valleys to alpine meadows to the spectacular yellow-walled canyon carved by the Yellowstone River. This is America's wildest, most geologically alive, and most biologically rich park.

The Grand Loop Road — a figure-8 of roughly 140 miles connecting the park's main attractions — is the organizing spine of any Yellowstone visit. Old Faithful and the Upper Geyser Basin should be on every itinerary: the boardwalk loop around Old Faithful connects a dense collection of geysers, hot springs, and fumaroles — Morning Glory Pool, Castle Geyser, and Grand Geyser (the world's tallest predictable geyser at 200 feet) among them. Grand Prismatic Spring, a short walk from the Midway Geyser Basin parking area, is more spectacular from the overlook trail on the hillside above — a recent addition to the trail system that finally provides the bird's-eye view visitors had been improvising for years. The Grand Canyon of the Yellowstone offers two of the most dramatic waterfall viewpoints in the Rockies: Upper Falls and the thundering 308-foot Lower Falls, viewed from Artist Point — one of the most painted and photographed scenes in American art history. Lamar Valley on the park's northeast side is the best wildlife watching corridor in North America, particularly at dawn and dusk when wolf packs from the Lamar Canyon pack are frequently spotted by spotting-scope-toting "wolf watchers." The Norris Geyser Basin, the hottest and most thermally dynamic area in the park, features Steamboat Geyser — the world's tallest active geyser at over 300 feet, erupting irregularly. Hiking trails from the backcountry of the Bechler region to the Seven-Mile Hole trail into the Grand Canyon offer wilderness adventure far from the crowds.

Yellowstone's wildlife is the stuff of legend. The park's bison herd of 4,000-plus animals is the largest on public land in the world and a genetic treasure — descended from the last surviving wild herd that persisted in Yellowstone when commercial hunting eliminated all others by the 1880s. Grizzly bears are routinely spotted in the Hayden and Lamar valleys, the Tower-Roosevelt area, and near berry patches in late summer. The 1995 wolf reintroduction — 31 wolves released, now a self-sustaining population of 100-plus — is one of conservation's greatest successes and has demonstrably changed the behavior of elk and even the course of rivers through a cascading ecological effect called a trophic cascade. Elk rut in September and October fills the Madison and Mammoth areas with bugling. Pronghorn, moose, coyotes, black bears, river otters, and trumpeter swans are regularly seen.

The park is open year-round, but most roads close November through April (except the Mammoth to Cooke City corridor). The $35 vehicle entrance fee is valid for seven days. Summer traffic is severe — arrive before 7 a.m. at popular sites like Old Faithful and Grand Prismatic or expect long waits. Timed-entry permits were piloted in 2023; check the NPS website for current requirements. Camping is available at 12 campgrounds; Grant Village, Bridge Bay, and Canyon campgrounds can be reserved through Recreation.gov. The historic Old Faithful Inn (1904) is the park's iconic lodging — book 6-12 months ahead for summer.

Yellowstone has five entrances. The most popular is the South Entrance via Grand Teton NP and Jackson, Wyoming. The West Entrance at West Yellowstone, Montana, is also heavily used. Bozeman Yellowstone International Airport (BZN) is the closest major hub (90 miles north). Jackson Hole Airport (JAC), inside Grand Teton NP, is the only commercial airport within a national park in the US. Salt Lake City (SLC) is about 5 hours from the South Entrance. Amtrak does not serve the Yellowstone area — a car is essential.

Stay at least 100 yards from wolves and bears, and 25 yards from all other wildlife including bison — despite their slow appearance, bison charge and gore visitors every year. Old Faithful's predicted eruption window is posted at the visitor center and on the NPS app — arrive 20 minutes early. The Grand Prismatic overlook trail is a short, worthwhile detour from the main boardwalk. Cell service is improving but still unreliable in many areas — download offline maps. For wolf and bear watching, binoculars and a spotting scope dramatically improve the experience. Lamar Valley wolf watching is best in early morning from late fall through spring when vegetation is low.