A group of sightseers on an underwater tour off the coast of Maui received a surprise when a group of humpback whales surrounded the submarine they were in.

The tour by Atlantis Adventures on Maui usually features lots of colorful fish, so to have the whales circling the submarine offered the ultimate adventure.

The whales appeared to be courting a female that stayed near the sub. The encounter lasted approximately 45 minutes, during which time the sub held its depth, not wanting to risk possible damage from bumping one of the mammals.

Below is a video clip of the close encounter.

The folks on board certainly got the experience of a lifetime, and something worth writing about on postcards.

-- Kelly Burgess