49 Fun Facts About Yellowstone National Park

Which US president signed the 1872 act creating Yellowstone, the world's first national park?

Ulysses S. Grant signed the act on March 1, 1872, but Congress attached no money: the park's first superintendent drew no salary and had to earn his living elsewhere.

Yellowstone lies mostly in which US state?

Wyoming holds 96% of Yellowstone, yet the park is older than the state: it was created in 1872, when Wyoming was still a territory 18 years away from statehood.

What do Yellowstone's geysers have that its quiet hot springs lack, making them erupt?

Constricted plumbing traps superheated water until the pressure blasts it skyward, while a hot spring's open channels let the heat escape. Yellowstone holds more than half of the world's geysers.

Old Faithful got its name from an 1870 expedition that noticed the geyser did what?

Erupted at regular intervals: the 1870 party named it on the spot for exactly that. The gap between eruptions has lengthened since, partly after earthquakes, yet park staff can predict the next one.

Which feature in Yellowstone's Norris Basin is the world's tallest active geyser?

Steamboat can hurl water more than 300 feet, but nobody can predict it: it lay dormant for 50 years until 1961, then erupted a record 48 times in both 2019 and 2020.

What gives Grand Prismatic Spring its bands of red, orange, yellow and green?

Mats of heat-loving microbes ring the spring, turning orange and red in summer and darker green in winter. The centre is too hot for most life, so it stays clear, deep blue.

Grand Prismatic is the world's third-largest hot spring; the largest, Frying Pan Lake, lies in which country?

New Zealand's Frying Pan Lake sits in the Waimangu valley near Rotorua, where a geyser once shot higher than any in Yellowstone before dying out over a century ago. Dominica's Boiling Lake ranks second.

What distinction does Yellowstone Lake hold in North America?

Largest freshwater body above 7,000 ft, it freezes over completely every winter and thaws only in late May or June, even though hot springs and geysers vent from its floor.

Yellowstone's 308-foot Lower Falls plunges into which canyon?

Grand Canyon of the Yellowstone: hot water and gases 'cooked' its lava rock soft, so the river carved it about 1,000 feet deep, and its yellow walls are quite literally rusting.

Wolves vanished from Yellowstone in the 1920s and returned in 1995; which animal makes up most of their winter kills?

Elk make up about 85% of winter wolf kills. While the packs were gone, park crews trapped and shot elk for more than 30 years to hold the herds down, until the culls ended in the 1960s.

The first wolves reintroduced to Yellowstone in January 1995 were captured in which country?

Canada supplied 14 wolves that January, and because wolves have a homing instinct, each family group was penned for weeks first so it would not simply head back north.

Which Yellowstone valley, nicknamed 'America's Serengeti', was the release site for the 1995 wolves?

Lamar Valley's wide, open floor makes its big animals easy to spot, which earned it the Serengeti nickname and still draws wolf-watchers with spotting scopes most days.

Which Yellowstone animal, cut to about two dozen survivors by 1902, now numbers in the thousands?

Bison were down to about two dozen by 1902; animals brought in from private herds helped rebuild what is now the nation's largest bison population on public land.

What finally tamed the 1988 fires that burned about a third of Yellowstone?

A September snowfall, arriving with rain on the 11th, did what $120 million of firefighting could not: crews saved lives and buildings but had little effect on the fires themselves.

Which organisation ran Yellowstone for three decades from 1886, before the National Park Service existed?

The US Army rode in after civilian superintendents, short of money and men, failed to stop poachers and souvenir hunters; its cavalry built Fort Yellowstone at Mammoth and stayed 32 years.

Harry Yount, appointed gamekeeper in 1880 to fight poaching, is remembered as the first what?

National park ranger in spirit: after a winter patrolling alone, Yount reported that no one man could protect the park, urged a ranger force and quit after 14 months.

Which painter on the 1871 Hayden Survey produced images that helped persuade Congress to create Yellowstone?

Thomas Moran was so changed by the trip that he began signing his work T-Y-M, for Thomas 'Yellowstone' Moran.

Who took the large-format photographs of Yellowstone on the 1871 Hayden expedition?

William Henry Jackson hauled fragile glass plates through the wilderness on mules; his prints proved that the old tall tales of geysers were true, and Congress created the park within months.

John Colter, credited as the first American to explore Yellowstone in 1807-08, was a veteran of which expedition?

Lewis and Clark discharged Colter two months early in 1806 so he could turn back west with fur trappers; his exact route is still debated, but his tales of 'fire and brimstone' stuck.

Fur trappers once knew the Yellowstone River as 'Yellow Rock' in which language?

French trappers called it Roche Jaune, a name widely believed to translate a Hidatsa one. The Hidatsa lived far downstream on the plains, so it was probably never about the park's yellow canyon.

Which president laid the cornerstone of the stone arch at Yellowstone's north entrance in 1903?

Theodore Roosevelt happened to be in the park on a two-week holiday while the arch was going up, so he was asked to lay the stone and the arch took his name.

Which phrase from Yellowstone's founding act crowns its north entrance arch?

For the Benefit and Enjoyment of the People crowns an arch built partly because officials felt the new rail stop at Gardiner gave so famous a park too plain a front door.

The Old Faithful Inn, built over the winter of 1903-04, is one of the world's largest buildings made of what?

Logs and local stone went up over a single winter. When a firestorm swept the Old Faithful area in 1988, crews kept the giant timber roof wet with hoses and pumps and saved it.

At Mammoth Hot Springs, hot water dissolves limestone and lays it down again as terraces of which mineral?

Calcium carbonate is dissolved from limestone on the way up and dropped at the surface as travertine; the springs shift so often that the terraces can look different within a day.

The latest Yellowstone supereruption, which formed the present caldera, was roughly how long ago?

640,000 years is the long-quoted figure, though newer dating says about 631,000. When the emptied magma chamber's roof fell in, it left a caldera some 30 by 45 miles across.

What kind of geological feature beneath Yellowstone left a 500-mile trail of old calderas across the Snake River Plain?

A mantle hotspot stays put while the North American plate creeps southwest across it, so the oldest calderas in the trail, some 16 million years old, now lie hundreds of miles from the park.

Which federal agency leads the observatory that monitors the volcano beneath Yellowstone?

The US Geological Survey set up the Yellowstone Volcano Observatory in 2001 with the Park Service and the University of Utah; its scientists watch the ground rise and fall but do not consider an eruption imminent.

How did the 1959 Hebgen Lake earthquake near Yellowstone create a new lake?

A landslide that dammed a river: a mountainside fell across the Madison, burying a campground where most of the 28 victims died, and the water behind it rose into Quake Lake within weeks.

Isa Lake drains backwards across Yellowstone's Continental Divide: its west side flows where?

The Atlantic Ocean, though the lake may now spill both ways only at the height of the spring melt; road engineer Hiram Chittenden came upon it in 1891 while scouting a route from Old Faithful to West Thumb.

Yellowstone Lake's Fishing Cone became famous after an 1870 mishap in which a hooked trout was accidentally what?

Boiled in the spring: the trout slipped the hook, fell in and floated up dead moments later. Tourists then made 'cooking on the hook' a must-do stunt, until the park banned it.

Which river flows through Yellowstone's Upper Geyser Basin, right past Old Faithful?

The Firehole runs through three geyser basins and is warmed by their runoff: one dormant crater alone pours more than 4,000 gallons of hot water into it every minute.

Which Yellowstone feature is a hot spring so acidic that it dissolves the rock around it?

A mudpot's acid rots the surrounding rock into clay, and iron oxides tint the mud pink, beige and grey, which is why the best-known ones are called paint pots.

Which tree species covers about 80% of Yellowstone's forested area?

Lodgepole pine has bark too thin to survive a blaze, yet many of its cones stay sealed for years until a fire's heat opens them, so the burned forest in effect replants itself.

In 1978 Yellowstone became one of the first what?

World Heritage Site status came in 1978, the first year UNESCO named any; by 1995 the park was on the 'in danger' list as well, though it has since come off.

Which tribe, fleeing American troops in 1877, spent 13 days crossing Yellowstone and ran into some 25 tourists?

The Nez Perce took several of those visitors captive on the way, and two tourists were killed; the flight ended that October in a last battle just 40 miles short of the border they were running for.

Which invasive fish threatens the native cutthroat in Yellowstone's largest body of water?

Lake trout turned up there in 1994, probably through an illegal release; the irony is that the government itself had planted the same fish in other park lakes back in 1890.

Which bird, North America's largest waterfowl, survived in the lower 48 only as about 70 birds around Yellowstone by the 1930s?

Trumpeter swan numbers had been cut that low by hunting and habitat loss; the holdouts around Greater Yellowstone's hot springs became the seed stock for the species' recovery across the country.

Which stone, quarried at a cliff in Yellowstone, was traded by prehistoric people as far as Ohio?

Obsidian from Yellowstone's cliff was prized for its razor edge and traded farther than any other in the country: about 90% of the obsidian in Ohio's Hopewell burial mounds came from it.

Which national park lies 10 miles south of Yellowstone, linked by the John D. Rockefeller Jr. Memorial Parkway?

Grand Teton owes much of its valley floor to Rockefeller, who from 1927 bought 35,000 acres through a front company so sellers would not raise their prices, then gave the land to the nation.

Which president signed the 1916 act creating Yellowstone's keeper, the National Park Service?

Woodrow Wilson signed the Organic Act on August 25, 1916; until then each park was run on its own, and the new bureau was handed 35 parks and monuments to look after.

In June 2022, what forced Yellowstone to close every entrance and clear out its visitors?

Record flooding followed heavy rain and a fast spring thaw; rivers tore out roads and bridges, and the north-east entrance road stayed shut until October.

Hundreds of Yellowstone visitors once gathered nightly to watch bears feed at what?

Garbage dumps doubled as nightly bear shows, but bears hooked on human food lost their fear of people and kept injuring visitors, so around 1970 the park shut the dumps and brought in bear-proof bins.

Shoshone Lake in Yellowstone is thought to be the largest lake in the lower 48 states that cannot be reached how?

By road is the one way you can't arrive: visitors hike in or paddle up the Lewis River from Lewis Lake. The lake held no fish at all until 1890, because Lewis Falls blocked the way upstream.

Yellowstone was honoured with its own coin in 2010 under which US Mint program?

America the Beautiful Quarters were issued in the order the sites were first protected, so the first national park got only the second coin: Hot Springs, Arkansas, reserved in 1832, came first.

The Tukudika, a Shoshone band who lived in what is now Yellowstone, took their name from eating which animal?

Bighorn sheep: Tukudika means 'eaters of the mountain sheep'. Shoshone bands were often named for a staple food, which is why another band was known as the salmon eaters.

Which railroad brought the first trainloads of tourists to Yellowstone's doorstep in 1883?

Northern Pacific trains stopped a few miles short at Cinnabar, where passengers climbed onto horse-drawn coaches; the rails only reached the park gate at Gardiner in 1903.

What were private visitors officially allowed to bring into Yellowstone for the first time in 1915?

Automobiles and horse teams made uneasy road-mates, and the cars won: within two years horse-drawn coaches and wagons were banned from the park's roads.

Which Yellowstone summit, topped by a staffed fire lookout, is among its most popular day hikes?

Mount Washburn honours Henry Washburn, who climbed it in 1870 while leading the expedition that named Old Faithful; a fire-watcher spends each summer living alone on top.

West Thumb, the round bay on the western side of Yellowstone Lake, was formed by what?

A volcanic explosion long after the park's last supereruption left a caldera within a caldera, about the size of Oregon's Crater Lake; it filled with water and became part of the lake.