WATCH: Driver in Yellowstone Encounters Gray Wolf Pack Crossing The Road.

Note: The video below does contain a very brief moment of strong language.

One universal truth about visiting Yellowstone is that you never know what you’ll see.

One lucky driver in Yellowstone recently was driving in the park at night heading to West Yellowstone and witnessed a pack of gray wolves crossing the road. Gray wolves in Yellowstone National Park are very elusive and according to the National Park Service, there are roughly only about 528 gray wolves in the park.

The driver was luckily able to catch the encounter on video showing 7 or 8 gray wolves reacting to the presence of a human. The wolves did not appear concerned, but rather curious about the vehicle. The sighting occurred just before Gibbons Falls in Yellowstone, and the driver was lucky enough to watch the wolves for 15 minutes before they went on their way.

Gray wolves are currently an endangered species and it is illegal to hunt them anywhere they are found in the United States. The majority of gray wolves reside in Canada and Alaska.

While encountering a wolf in Yellowstone may be rare, encountering other wildlife is not. Just earlier this week, tourists got to see the brutal sight of a grizzly bear taking down a bull elk in the Yellowstone River.

For more information on that story and to see the video, check out the link below.

WATCH: This Yellowstone Grizzly Takes Down an Elk in Epic Wyoming Fashion