50 Interesting Facts About Yellowstone National Park

Last updated on May 12th, 2022

Yellowstone is an American National Park located largely in the northwest corner of Wyoming and extending into Montana and Idaho. The park is also home to half of the world’s geyser’s and hydrothermal features. Let us learn about its history, geography, features and much more.

Interesting facts about Yellowstone National Park  

1. Yellowstone National Park (Yellowstone) was the United States first national park and is considered by many to be the first national park in the world. It was established by an act of Congress and signed into law by President Ulysses S Grant in 1872.

2. The park is larger in size than Rhode Island and Delaware combined, covering almost 3,500 square miles. The park forms a rectangle with an irregular eastern side that is 63 miles in length from north to south and 54 miles wide from east to west.

3. Yellowstone is located in the northwest corner of Wyoming and extends into Montana and Idaho. It mainly consists of sub-alpine forest that is the last intact temperate ecosystem left on earth and is a part of the South Central Rockies eco-region.

Yellowstone National Park facts and history.
Yellowstone sign at the north entrance in Gardiner, MT. Image credit – pedrik

4. Yellowstone Lake (one of the highest elevation lakes in North America) is centred on the Yellowstone caldera which is the top of the largest super volcano on the continent. It is estimated that it has erupted several times in the last two million years.

5. If the super volcano on which the park is located erupted today it is estimated it would result in over 90,000 deaths instantly and would spread molten ash as far as 1000 miles away in a layer that could be up to 10 feet thick.

6. The massive caldera on which Yellowstone sits (formed by an eruption approximately 640,000 years ago) was discovered by NASA astronaut and geologist Bob Christiansen using high-altitude photography.

Yellowstone National Park on map

7. Yellowstone contains more than 10,000 hydrothermal features which represent the largest concentration in the world. Half of the world’s known geysers are located in the park, the most famous of which is the Old Faithful geyser, which are fuelled by ongoing volcanic activity.

8. The Old Faithful geyser used to erupt every hour but as a result of suffering earthquake damage over the years, it now erupts on average every 88 minutes (give or take 10 minutes). The gap between eruptions has been known to be as long as 3 hours on some occasions.

Hot Spring At Old Faithful
One of the hot springs, a short walk from Old Faithful at Yellowstone National Park. Image credit – paweesit

9. Old Faithful was named by Henry Dana Washburn on September 18, 1870. He was the leader of the Washburn expedition and found it when exploring the Upper Geyser Basin.

10. The earliest known photograph of Old Faithful while it was erupting was taken by William Henry Jackson during an 1872 survey of the park.

11. The world’s tallest geyser, Grand Geyser, is located in Yellowstone and can send mineral-rich water up to 300 feet into the air.

Night Sky at Yellowstone National Park. Yellowstone facts for kids

Steam from geysers adds drama to the night sky scene at Yellowstone National Park. Image credit – NPS Natural Resources

12. The tallest predictable geyser is called Steamboat and erupts twice a day for between 10 and 20 minutes sending water up to 200 feet into the air.

13. Yellowstone is subject to between 1000 and 3000 earthquakes annually and is one of the most seismically active areas on the continent. The last significant earthquake occurred there in 2017 with a 4.36 magnitude tremor.

14. The park contains the largest concentration of mammals in the lower 48 states and is home to over 285 species of birds. It is also home to over 1,350 species of flowering plants, 1,150 of which are native to the area. About four fifths of the park covered in forest, consisting mainly of lodgepole pines.

Bison Herd - Yellowstone National Park. facts about Yellowstone
Bison Herd – Yellowstone National Park. Image credit – paweesit

15. Yellowstone is home to the largest herd of bison in the world that still roam freely and is the largest public bison herd in the US. It is estimated that the herd is about 4,800 strong and originated from a population of 25 that survived the mass killings of bison of the 1800s. They mainly consist of the Plains bison subspecies. Yellowstone is the only place bison have lived continuously since prehistoric times.

16. The bison are subject to an annual cull because of a fear of the spread of a disease called brucellosis in the state of Montana. The cull has occurred every year in the past 17 years with 1,200 bison killed in 2017.

17. Gray wolves (Canis lupus) were returned to Yellowstone in 1995 after having being extinct in the area for over 70 years. The North American wolf population was estimated at 2 million in 1600 while today about 65,000 remain.

Bull elk resting near Blacktail Ponds
Bull elk resting near Blacktail Ponds. Image credit – Yellowstone National Park

18. Yellowstone is home to one of the only herds of elk known that do not migrate. The Madison River Valley, located near the park’s west entrance, offers such good grazing the elk don’t need to move in the winter months.

19. Yellowstone features a Obsidian Cliff, a mountain composed of a black volcanic glass called obsidian that is formed when a specific type of lava (felsic) cools. Native American peoples visited the site for centuries to quarry the obsidian which they used for trade.

20. The first presence of humans in the Yellowstone area has been dated back to at least 11,000 years ago. The evidence for this was the discovery of an obsidian projectile point in 1959, possibly a spear head, at Gardiner, Montana. It was found near the north entrance to the park and came from Obsidian Cliff.

Obsidian Cliff. Yellowstone National Park fun facts
A huge 60m slab of obsidian topped by rhyolite, Obsidian Cliff was likely created due to a massive lava flow in the past. This site was long an important quarry for Native Americans, who utilized the glass-like mineral for multiple tools and weapons and for trade. Obsidian from this site was found as far as Mexico and Ohio. Yellowstone National Park, Wyoming. Image credit – Wayne Hsieh

21. The earliest archaeological deposits in the park were found on the shores of Yellowstone Lake. These revealed traces of a camp that was over 9000 years old and it is believed that people camped near the lake on a seasonal basis.

22. The US Engineers office, located near the Visitors Center, was built in 1903 and designed by the same architectural body that commissioned Grand Central Station in New York. The office is nicknamed ‘The Pagoda’ for its unique green triangular roof and was also known as the ‘Temple of Truth’ since it housed a courthouse.

23. The oldest building that still stands in Yellowstone is the Lake Yellowstone Hotel. It is painted a bright buttercup yellow color and dates back to 1891.

24. Yellowstone is home to the oldest log cabin building in the world. Called the ‘Old Faithful Inn’ it was built during the particularly bitter winter of 1903-1904.

25. The Yellowstone River is the longest river in the continental US, at 692 miles, that has never been dammed. It is considered that the river provides the origin of the park’s name since the Minnetaree Indians called it Yellow Rock River, probably because of the yellowish rock formations that surround it.

How Yellowstone Got Its Name, Lower Falls
Most tourists see the east side of Yellowstone where the main geyser basins, including Old Faithful, are found. If they don’t go to the west side of the park they miss what I consider the highlight of the park’s features. This is The Grand Canyon of the Colorado. After the water of the Yellowstone River parks for awhile in huge Yellowstone Lake, it flows about eleven miles where it drops over two falls. Here we see the lower falls, and part of the rapids which cut out an amazingly deep gorge below it. Check out the cliff face on the right of the picture and note its color. That yellow rock is what prompted the Native Americans to give the area that name. Image credit – Don Graham

26. In 1988 approximately 36% (about 1,250 square miles) of the park was damaged by 51 separate fires that broke out. Over 25,000 people were involved in battling the blaze at a cost of over $120 million.

27. While many explorers and trappers came near the edges of the area where Yellowstone is now located, it was officially discovered by John Colter in 1807. He was part of the Lewis and Clark exhibition and discovered the area when he went looking for local Indians to trade with.

28. In an 1870 survey of Yellowstone a member of the party, Truman Everts, became separated from the parts and was given up for dead. After losing his horse and supplies he survived for 37 days by living on thistles after which he was finally found.

29. Before this, many trappers passing through the area that reported what they had seen (fire, brimstone, lakes and geysers) were not believed by the public because their tales seemed too fantastic.

30. At the time of the discovery of Yellowstone the only native year-round inhabitants of the area were a group of Indians of the Wind River Shoshone tribe that were known as The Sheepeaters.

Yellowstone National Park: geysers and hot springs
Yellowstone National Park: geysers and hot springs. Image credit – Maureen

31. In 1901 William F Cody, more popularly known as ‘Buffalo Bill’, founded the town in Cody in Wyoming reputedly because it was close to Yellowstone.

32. Cody also built and owned the Pahaska Tepee mountain resort which is located about 5 miles outside the park. It exists to this day and continues to operate as a mountain resort that is also open to the public for tours.

33. Yellowstone’s first gamekeeper was stationed at Tower-Roosevelt junction and was tasked with preventing the slaughter of animals in the park. He is regarded as the forerunner of modern day park rangers.

34. Yellowstone Lake contains the largest population of cutthroat trout in the US and was a popular fishing spot. Anglers would dip the trout they caught in a nearby hot spring to cook them but the practice was discontinued when an eruption badly burnt an angler in the 1920s.

35. In the early years of the park travel to Yellowstone was arduous and there were continuing conflicts with native Indians. Visitor number increased significantly with the arrival of the Northern Pacific railroad with a spur built to the northern entrance of the park.

Mammoth Hot Springs are the main attraction of the Mammoth District. These features are quite different from thermal areas elsewhere in the park. Travertine formations grow much more rapidly than sinter formations due to the softer nature of limestone. As hot water rises through limestone, large quantities of rock are dissolved by the hot water, and a white chalky mineral is deposited on the surface.
Mammoth Hot Springs are the main attraction of the Mammoth District. These features are quite different from thermal areas elsewhere in the park. Travertine formations grow much more rapidly than sinter formations due to the softer nature of limestone. As hot water rises through limestone, large quantities of rock are dissolved by the hot water, and a white chalky mineral is deposited on the surface. Image credit – paweesit

36. The first hotel in the park, at Mammoth, was opened in 1883. It was acquired by the railway in 1886 which then began to develop other accommodation in the park to promote tourism.

37. The US Army took over administration of the park in the same year and helped to protect it from poachers – particularly those hunting the only remaining bison in the country.

38. Private cars were allowed in the park from 1915 (on July 31, a Ford Model T became the first to legally enter the park) onwards and travel increased considerably as a result. Today Yellowstone is one of the most popular national parks in the US and sees over 3 million visitors annually. There were a record number of over 4,250,000 visitors in 2016.

facts about Yellowstone National Park.
A road through Yellowstone National Park. Image credit – Charles Willgren

39. Yellowstone has its own Grand Canyon that was formed by erosion caused by the Yellowstone River. Stretching over 20 miles it features walls that are over 1000 feet high with some of the best views in the park – particularly from Arist point.

40. There are a dozen developed campgrounds in the park as well as more than 300 backcountry campsites that are maintained by the National Parks Service that are dotted over the park’s more than 1000 miles of trails.

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