Delighted viewers were treated to a rare show in Alaska's Denali National Park recently after a playful grizzly bear decided to roll itself downhill.

The video was uploaded by David Pangborn on Sunday. On the video, those watching the bear's antics are clearly having a good time too.

"That's hilarious," giggles an onlooker.

As the camera pans back, it's obvious those watching are quite a distance away from the bear.

The video garnered lots of comments online including the observation that the bear may have simply been keeping viewers entertained, while its friends raided their tents!

"Wonder if he knew he was being watched and decided to ham it up a bit?" asked one YouTube commentator.

"That was so funny, it was almost unBEARable!" punned another.