The Lion Cubs' Big Swim in the Okavango from Chris Eckstrom on Vimeo.

You never know what you'll see during a photo safari, especially one led by Frans Lanting, a world-famous photographer with decades of experience photographing wildlife around the world. But even he notes that, "This is the most unbelievable lion encounter that I've had in my entire career."

Lanting's wife, Chris Eckstrom, was also on the safari. She is a highly talented videographer and captured the whole event as a pride of lions has a nerve-wracking time getting their litter of tiny cubs across the river. All the females worked together to help as best they could, even when it meant dragging one cub across the river by the tail.

Jaymi Heimbuch ( @jaymiheimbuch ) focuses on wildlife conservation and animal news from her home base in San Francisco.

Lion cubs take a hair-raising swim across a river
A drama plays out for a lion pride and their litter of tiny cubs as they try to make their way across the Okavango.