Move over jet skis: The new onboard gadgets the ultra-rich seek for their superyachts are submersibles.

• The world's super rich have increasingly sought out superyachts in recent years.
• One way the ultra-wealthy are now accessorizing their luxury ships is with a submersible.

Joyrides on jetskis while sailing the high seas on your giant yacht are so last year.

Now, the world's .01% are seeking submersible vessels to accessorize their latest superyacht purchase, The Washington Post reports.

In 2021, sales of superyachts —yachts at least 120 feet long — reached record levels during the COVID-19 pandemic, Insider previously reported.

And these luxury vessels have only become larger, along with the demand, as the number of billionaires has grown in the past few years.

"You have a mega-yacht, a super yacht — a submersible has become the next thing to have," Ofer Ketter, co-founder of SubMerge, which facilitates private submersible expeditions, told The New York Times.

Amazon founder Jeff Bezos was recently spotted sailing the Mediterranean Sea in his $500 million megayacht Koru, which is 417 feet long.

There are several other expenses the uber-wealthy may want to consider with the purchase price of a superyacht, which, according to the Post, can cost at least $10 million.

There's gas, maintenance, storage, insurance, and, of course, staff to take care of guests on board.

But they may also want to include a submarine to explore the deep seas with their friends.

"Yacht owners are, by and large, people who have an interest in the ocean," Patrick Lahey, founder of Triton Submersibles, previously told Insider. "They like to go places and experience new things, and there's nothing quite like seeing the ocean from the perspective of a submersible."

This interest from the ultrawealthy was highlighted earlier this year after the OceanGate submersible imploded in June, instantly killing all five passengers. The company offered seats to visit the sunken Titanic ship in its vessel, Titan, for $250,000 per passenger.

The disaster may have sparked more interest in extreme adventures from the wealthy, Phillippe Brown, founder of Brown and Hudson travel company, previously told Insider.

At Triton Submersibles, a vessel can cost between $2.5 million and $7 million, Insider reported.

Similarly, SEAmagine, another submersible company that began in 1995, sells vessels that accommodate 2 to 7 people and cost the same amount as Triton's submersibles.

One of the company's models, the Aurora-80, can reach depths of up to 3,300 feet.

Ian Sheard, a principal engineer at SEAmagine, told the Post the vessels aren't actually parked inside the yacht but instead rely on what he calls "the toy hauler," which is just a "shadow ship" that follows the superyacht and carries all the goods that can't fit on the main ship.

"Even after a thousand dives, it never stops being exciting," Charles Kohnen, co-founder of SEAmagine, told the Times.