Visitors at Grand Prismatic experience the steam and bright colors of the spring while taking photos and pausing to sit on a bench.

Grand Prismatic Hot Springs



Emergency Phone: Dial 911

Yellowstone is a wilderness filled with natural wonders that are also potential hazards. There is no guarantee of your safety. Regulations are strictly enforced to protect you and the park's resources.



Do not approach wildlife, no matter how tame or calm they appear. Always obey instructions from park staff on scene. You must stay at least 100 yards (91 m) away from bears and wolves and at least 25 yards (23 m) away from all other large animals - bison, elk, bighorn sheep, deer, moose, and coyotes. Do not feed any animals. It harms them and it is illegal.


  • Bison can sprint three times faster than humans can run.
  • They are unpredictable and dangerous.
  • Your best view may be from inside a hard-sided vehicle.
  • Every year visitors are gored and some have been killed.


  • Bears are dangerous. More information can be found on our bear safety page.
  • Visitors are required to keep all food and garbage stored in a bear-proof manner.
  • When viewing bears along roads, use pullouts and stay in your car.
  • If you have a surprise encounter with a bear, do not run. Slowly back away.
  • Carry bear spray and know how to use it.
  • If you are injured by a bear (regardless of how minor), or if you observe bear or bear sign, report it to a park ranger as soon as possible. Someone's safety may depend on it.


Wolves are not normally a danger to humans, unless humans habituate them by providing them with food. No wolf has attacked a human in Yellowstone, but a few attacks have occurred in other places.

Like coyotes, wolves can quickly learn to associate campgrounds, picnic areas, and roads with food. This can lead to aggressive behavior toward humans.

What You Can Do

  • Never feed a wolf or any other wildlife. Do not leave food or garbage outside unattended. Make sure the door is shut on a garbage can or dumpster after you deposit a bag of trash.
  • Treat wolves with the same respect you give any other wild animal. If you see a wolf, do not approach it.
  • Never leave small children unattended.
  • If you have a dog, keep it leashed.
  • If you are concerned about a wolf—it’s too close, not showing sufficient fear of humans, etc., do not run. Stop, stand tall, watch what the wolf is going to do. If it approaches, wave your arms, yell, flare your jacket, and if it continues, throw something at it or use bear pepper spray. Group up with other people, continue waving and yelling.
  • Report the presence of wolves near developed areas or any wolf behaving strangely.
  • We advise visitors not to handle wolf scat. Humans could possibly ingest Echinococcus granulosus eggs (the tapeworm responsible for Hydatid disease) from handling wolf scat.

To date, eight wolves in Yellowstone National Park have become habituated to humans. Biologists successfully conducted aversive conditioning on some of them to discourage being close to humans, but two have had to be killed.


  • Coyotes quickly learn bad habits like roadside begging. This may lead to aggressive behavior toward humans. Never approach or feed a begging coyote.


  • Ravens have learned to unzip and unsnap packs. Do not allow them access to your food.

Geothermal Dangers

Boardwalks and trails protect you and preserve delicate formations. You must stay on boardwalks and designated trails. Scalding water underlies most of the thin, breakable crust. Pools may be near or above the boiling temperature and can cause severe, possibly even fatal, burns.

  • Keep your children close to you at all times; make sure they understand the danger.
  • Pets are prohibited in thermal areas.
  • Swimming or bathing in thermal pools or streams, where water flows entirely from a thermal spring or pool, is prohibited. Where swimming is allowed, swim at your own risk.
  • Thermal waters may contain organisms know to cause infections and/or amoebic meningitis, which can quickly be fatal. Obtain more information at any ranger station or visitor center.
  • Toxic gases may exist at dangerous levels in some hydrothermal areas. If you feel sick, leave immediately.


Yellowstone's weather can change quickly and bring cold temperatures, high winds, rain and falling snow.

  • Be prepared for changing temperatures, storms, and emergencies.
  • Carry adequate clothing

  • Unless posted slower, the top speed throughout the park is 45 mph (73 kph).
  • Watch wildlife from pullouts. If you see wildlife while driving, do not stop or pause in the roadway.
  • Detachable side mirrors must be removed when not pulling trailers
Other Hazards

Falling Trees

Following the fires of 1988, thousands of dead trees, known as snags, were left standing in Yellowstone. These snags may fall with very little warning. Be cautious and alert for falling snags along trails and roadways, and in campsites and picnic areas. Avoid areas with large numbers of dead trees. Again, there is no guarantee of your safety.

Backcountry Safety

Please see our backcountry pages to learn important tips for staying safe in Yellowstone's backcountry.



Do not take risks while fishing, wading, or crossing streams: park waters can be deceptively cold and swift.


Yellowstone's East Entrance road crosses 20 avalanche paths through Sylvan Pass. Avalanches also occur in other park locations. Additional information on avalanches can be found online at:


More Information

This page provides the basic rules at a glance. It is not comprehensive and should be used only to obtain a familiarity with some of our important rules. You will find additional rules defined in more detail on our Rules & Regulations Page and Laws & Policies.

Did You Know?