Seabourn has announced it will offer submarine excursions for the first time aboard its new fleet of expedition cruise ships.

The adventures into the deep will be operated aboard custom-designed submarines that will operate excursions for an additional charge from the line’s two upcoming ultra-luxury purpose-built expedition ships.

Seabourn Venture is due for delivery in 2021

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Both Seabourn Venture and her yet-to-be-named sister ship will carry the U-Boat Worx Cruise Sub 7 subs designed specifically for Seabourn.

Each battery-powered sub will carry six guests as well as one pilot, who will guide the journey up to 300 meters beneath the surface to explore sunken wrecks, reefs, and view marine wildlife in their natural habitat.

Guests will be seated in two clear acrylic spheres flanking the center pilot’s station and each set of three passenger seats will be mounted on a rotating platform that can turn for the best sightlines.

And because these are Seabourn subs, they’ll feature embroidered leather upholstery, two air conditioning systems, a Bluetooth stereo system, and even a champagne chiller for guests looking to toast their voyage of discovery.

“The undersea world is often considered as the last great frontier on Earth, with more than 80 percent of the underwater realm remaining unmapped, unobserved, and unexplored according to the U.S. National Oceanic and Atmospheric Administration,” said Robin West, Vice President of Expedition Operations for Seabourn.

Seabourn Venture will offer cruises in the Arctic and Antarctica during her first year

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“With these subs, we’re going to take our guests to places that few have ever seen firsthand, leaving them with a perspective on the world around us that is jaw-dropping and will create stories to last a lifetime,” he added.

To maximise the guest experience, the subs will be outfitted with a host of optional equipment, such as a 4k underwater video camera system to record the world outside while an internal video recording system will capture imagery of guests inside.

Video footage can then be downloaded and projected on large screens in the Discovery Center during lectures aboard the ships.

A six-function manipulator arm capable of lifting up to 32 kg (about 70 pounds) will also be mounted on the side of the subs. They will be equipped with underwater LED flood/spot lights, imaging sonar that acts as a second set of eyes, and an advanced underwater tracking and navigation system.

Seabourn in a press release said the subs will operate several times per day in suitable destinations around the world, from Seabourn Venture (due for launch in 2021) and her unnamed sister ship (due in 2022).

Cruise destinations already confirmed for Seabourn Venture include the Arctic and Antarctica, the Amazon, Caribbean, and Central and South America.

During her first year in service she will visit more than 150 destinations across the globe – many of which few travelers have ever been – and over 65 new or notable destinations with a multitude of new and compelling expedition experiences.