A group of lucky tourists had a whale of a time on recent cruise through the San Ignacio Lagoon in the Mexican province of Baja California.

Wildlife photographer Mark Carwardine captured images of a gray whale and her calf swimming up to a small boat full of tourists and allowing the humans to pet them.

The gray whale population of the Pacific, which is made up of a meager 150 whales, is listed as critically endangered by the International Union for Conservation of Nature, making this encounter extremely rare.

Despite their foreboding size, gray whales are known for being quite friendly.

“Locals here affectionately call gray whales "friendly ones" as they have an unusual tendency to approach whale-watching boats and check out the occupants,” writes the World Wildlife Federation.

Footage of the experience was also captured by drone that showed the enormous size of the these gentle giants compared to the small boat.