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50 free Yellowstone National Park trivia questions with answers — geography quiz, new questions added Aug 2026.
45 free Yellowstone National Park trivia questions with answers. Yellowstone National Park trivia lives in two places on BrainPickle. This page is the shorter set; the main quiz is Yellowstone trivia, with our deepest question pool on the topic and a source behind every answer.
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Q 01Which US president signed the 1872 act creating Yellowstone, the world's first national park?
Ulysses S. Grant
The act set the land apart 'as a public park or pleasuring ground for the benefit and enjoyment of the people', words later carved into the Roosevelt Arch.
Q 02Yellowstone lies mostly in which US state?
Wyoming
Small slices of the park spill over into Montana and Idaho, and its only year-round road entrance is at Gardiner, Montana.
Q 03Roughly what share of the world's geysers and hydrothermal features are found inside Yellowstone?
Well over half
They are powered by the Yellowstone Caldera, the largest supervolcano on the continent, which has erupted with tremendous force twice in the last two million years.
Q 04Old Faithful got its name from an 1870 expedition that noticed the geyser did what?
Erupted at regular intervals
Nathaniel Langford's party watched it spout nine times during their stay; today it goes off on average every 92 minutes.
Q 05Which feature in Yellowstone's Norris Basin is the world's tallest active geyser?
Steamboat
Its major eruptions can throw water more than 300 feet into the air, but the wait between them has ranged from three days to fifty years.
Q 06What gives Grand Prismatic Spring its bands of red, orange, yellow and green?
Mats of heat-loving microbes
The bands shift with the seasons: orange and red in summer, dark green in winter, depending on the ratio of chlorophyll to carotenoids.
Q 07Grand Prismatic Spring is the largest hot spring in the United States and ranks where in the world?
Third
Only Frying Pan Lake in New Zealand and Boiling Lake in Dominica are bigger.
Q 08Yellowstone Lake sits at 7,732 feet. What distinction does it hold in North America?
Largest freshwater body above 7,000 ft
It freezes over by early December under ice nearly three feet thick and can stay frozen until late May or early June.
Q 09The tallest waterfall in the park, the Lower Falls of the Yellowstone River, drops how far?
308 feet
The park counts 290 waterfalls of at least 15 feet, and it also has one of the world's largest petrified forests.
Q 10Gray wolves returned to Yellowstone in 1995 after being wiped out from the park in which decade?
1920s
The Park Service kept its predator-control policy going until 1933, by which time elk numbers were exploding and aspen and cottonwood were being grazed to death.
Q 11The first wolves reintroduced to Yellowstone in January 1995 were captured in which country?
Canada
Fourteen animals from packs near Jasper National Park in Alberta arrived in two shipments and were released into acclimation pens in the Lamar Valley.
Q 12Which Yellowstone valley, nicknamed 'America's Serengeti', was the release site for the 1995 wolves?
Lamar
It remains one of the most reliable places in the world to see wild wolves, home to the Lamar Canyon and Junction Butte packs.
Q 13Yellowstone's bison herd, the oldest public herd in the US, descends from how many survivors of the 1800s slaughter?
23
They hid out in the park's Pelican Valley; the herd numbered roughly 4,800 by 2020.
Q 21Which president laid the cornerstone of the stone arch at the park's north entrance in 1903?
Theodore Roosevelt
He happened to be visiting during construction and was asked to do the honours, which is how the arch took his name.
Q 22What phrase from the 1872 act creating the park is inscribed on top of the Roosevelt Arch?
For the Benefit and Enjoyment of the People
The arch cost about $10,000 and stands at the only one of the park's five entrances open year-round.
Q 23The Old Faithful Inn, opened in 1904, holds what record?
Q 14The great Yellowstone fires of 1988 burned roughly what portion of the park?
A third
On September 8 the entire park closed to non-emergency personnel for the first time ever; the flames were only finally tamed by snow and rain three days later.
Q 15Which branch of government ran Yellowstone for three decades from 1886?
The US Army
Troops built Camp Sheridan, later Fort Yellowstone, at Mammoth Hot Springs, and many of their patrol and anti-poaching practices were adopted by the Park Service.
Q 16Harry Yount, appointed gamekeeper in 1880 to fight poaching, is remembered as the first what?
National park ranger
A peak at the head of the Yellowstone River is named for him.
Q 17Which painter on the 1871 Hayden Survey produced images that helped persuade Congress to create the park?
Thomas Moran
He was so transformed by the trip that he began signing his work T-Y-M, for Thomas 'Yellowstone' Moran.
Q 18Who took the large-format photographs of Yellowstone on the 1871 Hayden expedition?
William Henry Jackson
Ferdinand Hayden warned lawmakers that without protection, 'vandals' would despoil the wonders 'in a single season'.
Q 19The first American known to enter Yellowstone, in 1807-08, was a veteran of which expedition?
Lewis and Clark
John Colter described a sulphurous geothermal area as 'hell', and Washington Irving's nickname 'Colter's Hell' stuck.
Q 20The English name 'Yellowstone' is a translation of a river name from which Native American language?
Hidatsa
Other tribes had their own names: 'land of steam' in Crow and 'boiling earth' in Nez Perce.
Largest log hotel in the world
It was built over a single winter from local lodgepole pine and rhyolite, and opened with electric lights and steam heat.
Q 24Mammoth Hot Springs' terraces are built from travertine, which forms as hot water deposits what mineral?
Calcium carbonate
More than two tons of it flow into Mammoth in solution every day, dissolved from limestone along the fault that feeds the springs.
Q 25The latest Yellowstone supereruption, which formed the present caldera, was roughly how long ago?
640,000 years
It produced the Lava Creek Tuff; the largest of the three cycles, 2.08 million years ago, formed the Island Park Caldera.
Q 26What geological feature beneath the park left a trail of calderas across the Snake River Plain?
The Yellowstone hotspot
The North American plate has drifted southwest over it, so the oldest calderas in the chain lie in Nevada and Oregon.
Q 27Which body monitors volcanic activity beneath the park and does not consider an eruption imminent?
The Yellowstone Volcano Observatory
The plateau has risen as fast as 150 millimetres a year, which geologists track as an indirect gauge of magma pressure.
Q 28The magnitude 7.2 Hebgen Lake earthquake of 1959, just outside the park, created a new lake how?
A landslide that dammed a river
Quake Lake still sits behind the slide; the earthquake killed more than 28 people and remains Montana's deadliest.
Q 29Isa Lake, straddling the Continental Divide at Craig Pass, drains to how many oceans?
Two
Oddly, its east side flows to the Pacific and its west side to the Gulf of Mexico, the reverse of what you would expect.
Q 30Yellowstone Lake's Fishing Cone geyser is named for an 1870 story about a trout accidentally being what?
Boiled in the spring
Walter Trumbull wrote that the fish 'darted about with wonderful rapidity' before rising to the top, dead.