Here are the most fascinating innovations in underwater travel

Two-thirds of our world is made up of water, which is why travel operators are starting to integrate underwater attractions into travel. It's the next frontier in the travel industry, as the area underneath our oceans has largely yet to be explored.

There is already an array of underwater restaurants, resorts, tours, and transportation available around the world today— and that's bound to grow even more in the future.

Here are some of the most fascinating innovations in underwater travel.

The "lover deep" submarine 

● Underwater transportation

One of the biggest underwater tour operators is Atlantis Adventures,which hosts Submarine Cruises where tourists can explore the waters of destinations like Hawaii, Barbados, Aruba, and Catalina Island through recreational submarines that dive through sea life. 

But besides submarine tours, there's a new market for privatized submarine experiences. British travel company Oliver's Travels created a specially adapted submarine in St. Lucia known as Lovers Deep, an underwater vessel where couples can spend the night in a private accommodation. The submarine, which is already available for use, is staffed by a crew of three, a captain, chef, and butler, and can be taken to locations chosen by the customer.

It's not cheap, at £175,000 per night ($274,694), but each interior of the private submarine room is set to be designed and manufactured to your specifications and includes a two-person bathroom and double bedroom with ocean views. Speedboat transfers come with the package, but you can also request helicopter transfer with a beach landing through the company's Concierge Service. 

Scientists are also working on creating a high-speed supersonic submarine as a means of passenger transport. A group of Chinese scientists have been developing a technology to create a submarine that can travel from Shanghai to San Francisco in less than two hours, according to the South China Morning Post. However, before the technology can be completed an underwater rocket engine will need to be created to allow for the long range needed for the vessel, according to the International Business Times. 

● Here are few of the most fascinating underwater transportation that you might have never heard of

1. Underwater seaplane

One of the most extraordinary features of the catamaran is the Necker Nymph, the latest marine exploration toy, designed especially for Virgin Limited Edition. It is an electrical submersible ship, in which two passengers seated next to an experienced pilot can dive to depths of 90 feet for up to two hours with a speed of 6 knots to explore the radiant underwater beauty of the British Virgin Islands. 

A friendly and expert crew of six will ensure that your vacation aboard the Necker Belle is a unique opportunity for fun and pleasure with luxury in an idyllic corner of the Caribbean. But if you want to rent it you must hurry, because recently Sir Richard Branson has put the ship up for sale. The price? Around 11.6 million.

2.Scubster Pedal Sub

Scubster, the Schwinn of the deep, is a man-powered submarine that can get up to 6 mph under the sea, which is just fast enough to not feel completely stupid, and still work up a sweat.

3.Spymaster One-Man Mini Sub

Spymaster, describing itself as "London's leading spy shop," does not advertise the price of any of their items, but outside sources confirm this diminutive aqua scooter costs a little under $20k. If the prospect of an underwater Vespa appeals to your sensibilities—and you don't mind being alone—this may be the sub of choice for you.

4.DeepFlight Dragon

Though the combination of the phrases "all-electric" and "underwater" may cause some worry, the hover-capable DeepFlight Dragon is one of the premier mini-subs on the market, and can go for six hours on one lithium battery charge.

5.Subversive Mini Cruises

This mini jet ski is the latest and greatest aquatic accessory. The Seabob Cayago F7 is not what you would imagine a jet ski to be; instead of being a giant, heavy vehicle, you must hook it onto the back of your truck.

When the warm weather hits, you will want to hit the beach to catch some rays. You can use this Seabob to travel up to 9 miles an hour, both on top of the water and underneath it. Of course, since it can move speedily as you are submersed, it limits your depth—don’t try and go explore the depths of the ocean.

For your safety, all underwater models from Seabob are set to a maximum depth of 2.5 meters for the average user. However, scuba divers can set it to a depth of 40 meters.