What Lives At The Bottom of Old Faithful?

Written by Niccoy Walker
Updated: October 7, 2022
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Old Faithful is the “always on time” geyser in Yellowstone National Park. Millions of visitors flock around to watch water spew from the deep hole in the ground every year. Combined with the picture-perfect scenery of the Wyoming wilderness, this phenomenon is enough to be on anyone’s bucket list. What makes this geyser so unique, what lies beneath Yellowstone, and what lives at the bottom of Old Faithful?

What is Old Faithful?

Yellowstone National Park

Old Faithful is a highly predictable cone geyser in Yellowstone National Park.

©Susanne Pommer/Shutterstock.com

Old Faithful is a cone geyser located in Yellowstone National Park in Wyoming. It is one of nearly 500 geysers. Out of all 500 geysers, park rangers can only predict eruptions for six. Old Faithful is highly predictable and erupts every 44 minutes to two hours for over 20 years. This unique geothermal feature inspired Yellowstone to become the first national park in 1872. 

The Old Faithful is not the tallest or the largest geyser in the park, but it is mathematically reliable, with over one million eruptions recorded. In 1870, an expedition entered the Upper Geyser Basin and discovered this impressive water spout. In the park’s early days, Old Faithful was regularly used for washing laundry. People would place their garments in the crater and then wait for them to eject, perfectly cleaned by the hot water.

The temperature of the water inside the vent measures around 204° Fahrenheit, and the steam spilling out of the hole is around 350° Fahrenheit, well over the boiling point for water. So far, no one has fallen into the geyser, but over 20 people have died from falling in the nearby hot springs. Yellowstone features windy paths that cut through the unstable ground, scalding mud, and boiling water.

Many people don’t realize that beneath Yellowstone is a dormant super volcano, one of the largest in the world. It would be catastrophic if it erupted, possibly wiping out several states in the western United States.

Yellowstone Super Volcano

A supervolcano lies beneath Yellowstone National Park. It could be catastrophic to the country if it erupts.


The Yellowstone Caldera is located beneath Yellowstone National Park. This behemoth super volcano is much more powerful than the average volcano, with the ability to spew 2,500 times more material than what erupted out of Mount St. Helens. The caldera measures 43 by 28 miles and formed during the last three super eruptions: 2.1 million years, 1.3 million, and 640,000 years ago. Scientists predict these cataclysmic eruptions happen every 600,000 to 700,000 years.

If the Yellowstone Supervolcano erupts again, it will affect the entire world. It could kill millions of people, spew ash for thousands of miles, and potentially spark a mini ice age. Currently, there is no indication that the volcano will erupt soon. However, things can change rapidly. Experts believe the possibility of an eruption in the next few thousand years is exceedingly tiny. But it’s possible to go from seeing its usual activity to preparing for a super explosion in the 2030s.

The Old Faithful geyser is one of many geothermal vents atop this supervolcano. So technically, an enormous volcano lives below Old Faithful (though not actually living). Discover if there is anything alive at the bottom of this geyser. 

What Lives at the Bottom of Old Faithful?

Animals that live near volcanoes – thermophile

Extremophiles live at the bottom of Old Faithful. These organisms thrive in harsh environments like near-boiling water.


Microorganisms called thermophiles live at the bottom of Old Faithful. Thermophiles are heat lovers that make their homes inside the hydrothermal vents in Yellowstone. Also known as extremophiles, these organisms can survive in places most humans and animals cannot, like near-boiling temperatures inside super hot geysers. In fact, they need harsh environments to thrive. 

Individually, thermophiles are invisible to the naked eye. But when they come together in large groups (trillions), as they do around Old Faithful, they appear as mats of color. You can find these colorful mats all over the park, especially near the hot springs. Visitors are captured by the vibrant shades of orange, red, and blue, stopping to take pictures. Little do they know the trillions of life forms that make up these photographic areas.

There may not be any dangerous or scary creatures living at the bottom of Old Faithful, but wildlife is plentiful in Yellowstone State Park. Find out what animals live around this spectacular geyser and on top of one of the largest supervolcanos in the world. 

What Animals Live Near Old Faithful?


Bison, rattlesnakes, gray wolves, and grizzly bears are some of the most dangerous animals in Yellowstone National Park.



Yellowstone is the only place in the country where bison have lived continuously since prehistoric times. They roam freely across the vast landscape, attracting millions of visitors annually. Many people underestimate these wild animals because they look docile. But, in reality, bison are the most dangerous animals in Yellowstone. Bison gorge at least one person per year by charging without warning. 

Prairie Rattlesnake

The prairie rattlesnake is the only dangerously venomous snake in the park. This species is more defensive than it is aggressive and has only bitten two people in the park’s history. This snake can grow to more than 48 inches in length and is the largest reptile species in the park. You will most likely see it in warmer, drier places in Yellowstone. 

Grizzly Bears

Yellowstone is home to two species of bears: black bears and grizzly bears. There is a healthy grizzly bear population of around 700 within the park boundaries. There are more grizzly bears in the park; they are bigger and much more aggressive than black bears. While there have only been eight bear attacks in the area, you should still use proper precautions around these dangerous animals. Don’t feed them, keep your distance, and always be aware of your surroundings. 

Gray Wolves

Wolves inhabit most of the park, and the best place to watch them is on the northern ridge. Wolves are not typically dangerous to humans; no wolves have attacked a human in Yellowstone. But they are still wild animals, and you must keep your distance. Park rangers strictly enforce the rule regarding feeding wildlife. When you feed a wild animal, you help habituate them to humans, leading to the possibility of future attacks and fatalities.

The photo featured at the top of this post is © iStock.com/BigshotD3

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About the Author

Niccoy is a professional writer for A-Z Animals, and her primary focus is on birds, travel, and interesting facts of all kinds. Niccoy has been writing and researching about travel, nature, wildlife, and business for several years and holds a business degree from Metropolitan State University in Denver. A resident of Florida, Niccoy enjoys hiking, cooking, reading, and spending time at the beach.

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