What's your happy place? If it involves a calm blue sea and the sound of softly crashing waves, an underwater hotel can bring your dreams to life. It's the ultimate in spa-like relaxation. Imagine sleeping with the gentle waves of the ocean lightly rocking your bed and a soft blue glow illuminating your view of exotic fish swimming past your window. It's all possible with an underwater room that's yours to rent.

More and more luxury hotel chains are offering underwater locations or underwater elements within their best above-ground hotels. The Hilton and the Radisson are among leading hotel corporations who are beginning to offer guests the option of diving deep into their own subterranean suites (or at least giving guests the expensive and impressive illusion that their rooms are under the sea).

The best of the best are hotels that are authentically below sea level and using this status to their advantage. Some hotels have been designed around the concept of underwater luxury, so they are entirely themed and structured to suit guests with underwater ambitions. Many new underwater hotels are just in their conceptual stages or have recently begun construction. This is a sign of a hot hotel trend earning its own niche in the luxury travel business. You could say underwater hotels are going mainstream, with increasingly affordable prices to prove it.

Take a look at these 20 top underwater spaces for you to explore the next time you and your friends feel like taking those oceanside resort plans to a new deeper level.

20 Planet Ocean: Key West, Florida

This is one of the few items on our countdown that is still in the construction stage, but if you're taking a trip in the near future, it's worth checking up on. Planet Ocean resort is getting more polished and put-together by the day. However, its lack of completion had to land it (or 'sea' it) at last place on the list. If you want to feel good about living in luxury underwater, Planet Ocean could be a great choice for you and up to 11 of your friends. 10% of proceeds from each of the 12 guest rooms is invested into coral reef restoration projects!

The underwater hotel is also planning to host a variety of marine biology programs through sponsored college and university projects.

Now for the nitty gritty: each room is completely and entirely submerged in the waters of Key West, so guests must take a short series of safety precautions prior to getting comfortable. Scuba training isn't necessary because the rooms never go more than 30 feet below sea level, but highly-trained crew will always be present to ensure everyone is safe and happy. Keep an eye on Planet Ocean for a very deep and eco-friendly voyage in your future.

19 Burj Al Arab Jumeirah: Dubai, UAE

If you've ever seen a picture of Dubai's iconic skyline, then you've seen the Burj Al Arab Jumeirah hotel. It's the sky-scraping tower building right in central Dubai, shaped kind of like a sail billowing in the wind. This hotel is just as luxurious on the inside as it is well-known on the outside. Around the world, it's famous for its state-of-the-art interior design, first-class amenities, and five-star restaurant.

It's the restaurant that we're most interested in for the purposes of this list. You can spend your night dining the hours away in Burj Al Arab Jumeirah’s one-of-a-kind dining experience, the Nathan Outlaw restaurant. Tables are surrounded by a floor-to-ceiling aquarium, offering guests an ambiance right out of The Little Mermaid.

Live your Ariel fantasy while dining on Dubai's best seafood dishes. They're fresh from local waters and as diverse as oyster ceviche and white sturgeon caviar. We can almost taste it all! Only the best is served in this ultra-glamorous underwater space.

Its guests have included it girls like Kendall Jenner, Gigi Hadid, and Selena Gomez, just to name a few. Unfortunately the sleeping quarters, while extremely luxurious and overlooking the entire elegant downtown core of Dubai, are not underwater but high above in the sail-like tower of the hotel. That's why the fantastically-opulent Burj Al Arab Jumeirah isn't higher on our list of must-see underwater destinations. It's still worth a visit if you want unbeatable seafood in an under-the-sea environment, but check out the following destinations if you're looking for a more authentic underwater experience that extends past your dinner and into your dreams.

18 Amphibious 1000: Doha, Qatar

Amphibious 1000 calls itself a semi-emerged floating hotel, still in conceptual stages in one of Qatar’s artificial reefs. Any trip to Qatar within the next ten years won’t be complete without a visit to this soon-to-be-finished high-concept hotel.

It’s designed to feature a part on land and parts reaching out to (and under) the sea. There will be 80 sea pods, called jellyfish, which will float partially submerged beneath the surface of the water. This will give guests incredible views of the artificial reef and its real aquatic life swimming in it. It will also give them 350-degree panoramic views of the landscape and jellyfish pods surrounding them.

All of the pod units are self-contained suites. A relaxation room sits at the top of each pod, 5.6 meters above sea level. At 3.5 meters above sea level are the pods’ bedrooms and bathrooms. At 1.4 meters is a floor meant for casual daytime use, with a kitchen and a second bathroom, while down under at 3 meters below sea level is a floor meant for romantic evenings, complete with a private aquarium lounge.

The units are situated in a half-circle around the hotel’s main tower. This tower contains all the extras a hotel guest could want. A reception area, a restaurant, and more will be available to guests staying in every single one of the 80 floating pods.

17 Three Spirits Floating Hotel: Pacific Ocean

Three Spirits is another conceptual hotel taking the idea of floating pods to the next level. Not only does its accommodations float, but they soar through water, moving from one ocean destination to the other, kind of like a futuristic cruise ship.

The hotel was developed by architect Filip Kurzewski to meet the growing marine tourism demand in the Pacific. Kurzewski's educational background includes certification from the Warsaw University of Technology, so you can trust that this yet-to-be-made floating hotel is incredibly high-tech. It's made up of three distinct ships that can work independently as well as having the potential to function together as one.

Fans of Star Wars and Star Trek can think of the Three Spirits as their own personal Millennium Falcon or Starship Enterprise at sea, navigating and exploring the vast surface of the Pacific Ocean. Guests at the Three Spirits will be in for more than a fun ride. The interior spaces are being designed to feature resort attractions like a theater and a casino for travelers to try their luck as they ride the waves. You can also look forward to a safe underwater experience in the hotel's diving capsules—no wetsuit required. The entire capsules will be submerged into the ocean's depths for your viewing pleasure.

16 Radisson Blu: Berlin, Germany

Leave it to Berlin to serve you out-of-the-box creativity and romance. This historic German capital city is home to iconic architecture and cosmopolitan culture. Its Radisson Blu hotel is classically chic with an aquatic twist: a gigantic water cylinder plunging up through its central lobby.

The cylinder is a fully-functional aquarium with vibrant exotic fish and the occasional appearance from a deep-sea diver. It’s got over a ton of water and it’s all lit up blue, hence the hotel’s name. The idea of putting this huge aquarium in the center of this space is to give guests in rooms encircling the lobby the illusion of an underwater experience.

From the inside of each cozy and stylish room, you can gaze out through a window that opens onto your own personal view of the indoor aquarium. This is a magical experience for anyone wanting to see fish float by their room without being actually submerged underwater themselves.

Despite the underwater element of this hotel being a clever effect instead of the real deal, its prime location in Berlin helps it earn its place on this list. Radisson Blu is located right in the center of the city, giving guests walking-distance access to Alexandraplatz, a range of world class museums, and the city’s famous river. Worth a visit anytime you’re in Berlin!

15 Utter Inn: Vasteras, Sweden

The Utter Inn is an utterly unique item on our list. It’s a little Swedish sea hut quite unlike the array of tropical and Mediterranean resorts out there. Originally designed as an art piece by Swedish artist Mikael Genberg, this space is meant to look like a traditional Swedish house floating peacefully on the water.

It’s anchored into the middle of Lake Mälaren near the town of Västerås in Sweden. The only way to reach it is by swimming out or canoeing across the lake with your travel companions. As an added bonus, the Inn is canoeing-distance away from a small uninhabited island for you to explore. That’s like having your own private island along with your half-floating, half-submerged hotel room.

Inside the Inn is a small entryway, a little spiral staircase leads you (plus one potential guest) down into the sleeping space, complete with two beds, one utilitarian table, and waterproof windows overlooking the lake bed. This room is only open from May to October due to the ever-changing Swedish weather. Book your visit early for a good rate (just $75 per night!) and a great nautical time. And remember to look out for otters! Utter is Swedish for otter, so those sweet creatures are what this quaint little space is named after.

14 Water Discus Hotel: Dubai, UAE

Another entry from Dubai! No surprise, considering the city is such a modern mecca for all things luxury. The Water Discus Hotel is made up of two large discs, one above the water and one down below. The discs are connected by stairs and elevators in cylindrical tubes and feature a scattering of smaller discs just above the water's surface. One of the discs is a landing pad for helicopters that bring guests right onto the floating resort.

This is a great destination for any travelers who are passionate about diving. If that sounds like you, you'll be happy to hear that each of the hotel's 21 guest rooms is equipped with its own airlock and diving pad. If it doesn't sound like you, why not give underwater adventure a try? This hotel is a very safe place to have your first diving experience because of its many safety features. There's a decompression chamber for training and even classes run by the hotel to teach guests how to pilot underwater vehicles.

Take a drive on the bottom of the sea! Another perk to the Water Discus hotel is its location within a vibrant coral reef ready for you to explore. And with the right training and the hotel's help, you'll be in total control.

13 Bambu Indah Hotel: Bali, Indonesia

Have you ever dreamed of a vacation in sunny Bali? Add this hotel to your Bali to-do list. It's got the perfect blend of local charm and modern comfort. If you rent the Udang House suite, you'll gain access to spectacular ocean views right beneath your feet. It's got a tempered glass floor that is so crystal clear it'll make you feel like you're walking on water. The depths below the suite were once a Balinese fisherman's pond, featuring lively shrimp and a glimpse into true Indonesian agricultural wildlife. The rooms within Udang House itself are undeniably luxe and chic, so despite the fishy atmosphere beneath your feet, you're sure to feel like someone at the height of hotel luxury.

This location has the calm aquatic vibes of a high-end spa. It's easy to picture you and your main squeeze settling into the four-poster bed and gazing at the sea creatures below, feeling like you're floating on an ocean of comfort and style. Underwater wonders abound!

As a bonus, the main spaces of this hotel are just as unique. There are authentic rice paddies for you to wade through and bamboo bridges that make perfect scenic backdrops to your photos of Indonesian paradise. It's even got a natural swimming pool teeming with fish. If you find yourself wanting to dive through your hotel room floor and swim with the fishes, it's truly possible at the Bandu Inda.

12 Hotel H2O: Manila, Philippines

Hotel H2O offers the life aquatic in every element of its design. It's part of Manila's Ocean Park, a water wildlife theme park and educational center. Think of Seaworld having its own accommodations and then turn up the quality a few notches, and you have Hotel H2O.

Every room has at least one wall that is floor-to-ceiling sea life via a massive aquarium of local and protected species. Look out for schools of jellyfish floating along beside your bed. The accessibility of the sea life element of this hotel makes it an ideal destination for families including small children. Mesmerizing aquarium views and fun educational activities can turn a family's stay into a memorable learning experience.

Adults can find the aquatic aesthetic to be very relaxing. The free-flow rhythm of the aquarium walls inspire an inner calm that many TripAdvisor reviewers have appreciated. If you can't chill out in your room alone, visit Hotel H2O's Zenyu Eco-Spa. It's a one-of-a-kind relaxation space featuring the power of negative ions sourced from natural resources like virgin forests, waterfalls, hot springs, beaches, and mountains. Give yourself over to the spa staff’s expert techniques and feel yourself become as fresh and rejuvenated as the mists rising from the hotel’s ocean landscape.

11 RW Sentosa Ocean Suites: Sentosa Island, Singapore

Resorts World Sentosa offers 11 exclusive Ocean Suites for the luckiest of guests. Book well in advance to guarantee that you get a place in these popular rooms! They're each designed like a two-floor home, the second floor being above water and the first floor below.

On the upper level, you can enjoy an open-concept living room space equal to that in any five-star hotel. What makes this floor special is the outdoor patio and private Jacuzzi you can enjoy with your fellow traveler. On the lower level, you have a plush bedroom with an underwater view of the sea life the suite is submerged within. You can choose whether to raise or lower the viewing panel, so if sleeping with the fishes makes you dizzy or nervous, just close the panel when it's time for bed and relax.

This hotel is a step up from Manila's Hotel H2O (and a place higher on our list) because the view is not just any aquarium. It's the world's largest aquarium. Here, your perspective can include more than 40,000 marine fishes from the comfort and privacy of your hotel bed. It's also close to aquatic adventures, with the S.E.A. Aquarium and Adventure Cove Waterpark within walking distance.

10 Per Aquum Niyama: Huluwalu, Maldives

Per Aquum offers elegant interiors and pristine waters in the dreamy, steamy destination of the Maldives. It's hot outside but ultra-cool beneath the surface of the waters where many areas of this hotel are located.

Enjoy kaleidoscopic views of colorful fish and corals from your own room, the restaurant, the spa, and more. Moray eels and giant turtles call the Maldives home, so it's the perfect place for an underwater adventure.

Meet international travelers and get carried away in the wild watery atmosphere of this resort's special features. Up for some nightlife? Per Aquum is also home to the world's first underwater nightclub. Dance up a (tropical) storm before retiring to your five-star room for some blissful rest and relaxation. This hotel is known for its excellent service, including room service, so order a late night snack and fall asleep with the fishes.

Another great reason to stay at Per Aquum is its above ground amenities, which include private white sand beaches and crystal clear infinity pools. Anyone who aspires for social media stardom is sure to get Insta-famous with the photo ops that this resort provides. Suites average about $1,000 per night so it's not cheap, but can you really put a price on a once-in-a-lifetime experience? Your call.

9 Jules Undersea Lodge: Florida, USA

This hotel might be rustic compared to what you've seen so far, but it's just the beginning of your underwater options that are authentically and entirely under the sea. It's also an excellent option for anyone interested in seeing all the fantastic aquatic life thriving in Key Largo, Florida.

Jules Undersea Lodge has an unpretentious quality that extends even to the dinner offered—an underwater pizza delivery passed to you from one of the scuba-certified staff members. You can learn to scuba-dive yourself in the lagoon surrounding the lodge with the help of these friendly divers and hospitality workers.

“This is a once in a lifetime experience that must be taken advantage of if possible,” says a TripAdvisor reviewer from Boca Raton. “The fact they were able to hold a resort type scuba course was amazing.”

Another guest favorite is the night dive option where you and your fellow traveler can have a deep dip in the lagoon under the stars. If you'd rather cozy up together indoors, the lodge itself is perfect for couples. It offers exciting adventures along with privacy and authentic underwater hospitality, which is why this unique hotel cracks our top ten. And you can’t beat the price! Rates are as low as $85 per night.

8 Manta Resort: Zanzibar, Tanzania

The Manta Resort's underwater room is unquestionably a top ten underwater hotel option. It's both extravagant and private, showcasing unrivaled floating relaxation spaces designed to be shared between two people who are deeply (pardon the pun) in love.

This resort is worth screen-shotting and Snapchatting to the one you love the most. It could be your ultimate dream vacation destination to spend together. Like a stunning scene out of a James Bond movie, this hotel floats in the middle of a remote lagoon that you can reach only by speedboat or kayak. It's a Swedish-engineered structure that includes three distinct levels, all exclusively accessible to the couple who checks in. Even though it's sleek and modern, locally-sourced wood and cohesively-designed elements make the space seem like it's a natural fit in the surrounding landscape.

This hotel's particular location has very little light pollution from nearby cities, making the night's sky crystal clear and spectacular to view from Manta's top-level lounging area. By day, the wide open sunny skies make for great sunbathing in the very same lounge space. But the most exciting and romantic elements are below the surface—a near-360-degree view of corals, reef fish, and their predators. Lay back with your loved one and look out for the octopus who has made the hotel's anchor cords its home.

7 Anantara Kihavah Villas: Kihavah, Maldives

At this point, you might be forming the opinion that the Maldives have really cornered the market on underwater accommodations, and you wouldn't be wrong. Yet another magnificent Maldives hotel with elite underwater features is the Anantara Kihavah Villas.

Here, you'll get the full package of Maldivian luxury and adventure. Your own private villa, floating relaxation rooms, submerged communal guest spaces, an over-sea observatory, a holistic spa, natural soft-sand beaches, and more will all await you if you rent yourself a room in this glamorous space.

Villas are built to be unique, so you can choose just how underwater your experience will be. Perhaps a villa with an above-ground infinity pool will inspire your nights in Kihavah. Maybe you'd prefer a sandy sanctuary with real island charm.

A standout feature of this luxury hotel is definitely its restaurant (which we've pictured above). It's always a good time for wine, so take your time during your villa visit to check out the restaurant's exclusive underwater wine cellar. You can choose from wines originating in over 14 countries and aged to perfection. Order a glass or bottle with dinner at SEA, the hotel's subterranean restaurant. The executive chef has paired wine selections with the delicious menu items, including lobster fresh from the local fisheries. Just don't feel guilty if a lobster family swims past you while you chow down.

6 Lover's Deep: St. Lucia, Caribbean

Tacky but true. Guests at the Lover's Deep suites are encouraged to join the "mile low club" because their rooms are located deeply below sea level. Thankfully, the rest of the resort is completely free from bad taste. Everything is stylish, trendy, and contemporary—a real challenge when you consider the building regulations designers had to work within while outfitting rooms that can safely withstand shifting water pressures.

Lover's Deep is different from almost every item on our list because instead of having rooms tethered to anchors or built on poles extending below sea level, it offers rooms located within an authentic and technologically state-of-the-art submarine! During a typical stay, the sub travels through the bright blue waters of Caribbean islands including Montserrat, Martinique, St. Lucia, and the Barbados.

Every effort has been taken to make Lover's Deep a safe, private, and exclusive experience. A staff of just one captain, one chef, and one butler work aboard the submarine to keep things going swimmingly. Their own rooms are located far from the guest space, however, ensuring your privacy will be respected. Gourmet food, including oysters, caviar, and chocolate, is offered absolutely free of charge if you choose Lover's Deep as your honeymoon destination. Consider booking a room after asking yourself: how deep is your love?

5 Shimao Wonderland: Shanghai, China

Shimao Wonderland is a modern masterpiece of hotel design. It's been built into an abandoned quarry in the Sheshan National Forest between Tianmashan Hill and Hengshan Hill, making it a strong choice for any traveler who loves the uniquely luscious natural landscape of eastern Asia. Travelers can also enjoy the sites around the hotel itself. Surrounding the hotel is a deep lush riverbank, Heng Shan Tang urban area, traditional farmland, and the city's major Chen Hua Road.

Of course, you really don't have to venture beyond the hotel to have plenty of pleasure and excitement. Shimao Wonderland isn't called a 'wonderland' for no reason! It's China's very first large-scale themed project integrating residential, hospitality, leisure, and entertainment elements like theaters, cinemas, and sports arenas.

While part of this fantastical resort is residential apartments for lucky locals, much of it is a five-star hotel ready for you to dive in and claim your own suite. When we say dive, we mean it—Shimao's stunning semi-submerged location doesn't go to waste. Enjoy views of swimming fish and corals from the restaurant, spa, and throughout the sea-themed resort rooms. If you've ever tasted Chinese seafood, you know why this resort is a must-try.

4 Conrad Rangali Resort: Mandhoo, Maldives

Not only is the Conrad Rengali Resort renowned for its underwater elements, but it's also been voted Best Hotel in the World two times by the World Travel Awards. It's large and in charge, spread over two private islands joined by a footbridge that makes for some unmissable photo opportunities. The Indian Ocean is literally at your feet when you choose to stay and explore rooms at this world-famous resort. Yet again, your room style is your choice.

Features vary from suite to suite and include private gardens, sundecks, hot tubs, glass floors for better fish-observing, and/or direct access to your own private strip of one of the islands' beaches. The very most upgraded options include personal butlers at your service and spa treatment rooms within your own suite.

This means you wouldn't have to leave the comfort of your private space to get exfoliated or massaged, and more importantly, you wouldn't have to travel far from the massage table to your cushy bed once the treatment is done and your relaxation has reached new heights.

If you have energy to burn, take a turn on the islands' tennis courts and build up your appetite. Dinner is served in no less than 12 restaurants on the resort, but of course, we're most interested in the glass-enclosed underwater one. Dine the night away with seafood both on your plate and encircling the restaurant. It's sleek, chic, and has never sprung a leak.

3 Shark Suite: Paris, France

So far, we've shown you room options that let you sleep alongside fish, lobsters, jellyfish, turtles, and tropical corals. This option takes it to the next level. You know it, sharks.

Every week is shark week at the Shark Suite in Paris, France. It's well-designed, featuring a comfy circular bed and industrial decor accents, but the physical comfort might end there. The room is submerged 33 feet deep in a three-million-liter tank full to the brim with no less than 35 live sharks. If the idea of that doesn't put you on edge, you can consider yourself a true adventurer.

Brave travelers can book this unique room through Airbnb. It is Airbnb's very first underwater destination on offer and is proving to be very popular among tourists seeking extra-memorable experiences while they visit Paris. Just a wall of glass separates guests from these sharks. It's a great way to have a clear view for observing sharks up close, which you're likely never to get to do in the wild and live to tell the tale. You're safe in this suite, thanks to staff at the Paris Aquarium, located along with this room in a building that sits directly across from the Eiffel Tower. What more could you ask for?

2 Floating Seahorse Villas: Dubai, UAE

Dubai's Floating Seahorse Villas are nothing short of stunning. When it comes to high-class marine-style suites, you can't go wrong here. Would you expect anything less from Dubai? The only downside is that at this point (after a long conceptual design phase), these well-constructed wonders have gotten all booked up, years in advance. But we can dream! A Floating Seahorse villa is essentially a high-tech three-level hotel houseboat without a propulsion system. They are parked in their own patches of the Arabian Gulf not too far from central Dubai tourist destinations and business centers.

Think garden, patio, sunroof, lounge, and most of all, fully-submerged bedroom with floor-to-ceiling glass window walls. The views from within are like a scene right out of a mermaid story.

This option is also high on our list for those reasons along with its family-friendly vibes. Unlike your average hotel, underwater hotels seem to cater to honeymooners and romantic couples in general, but sometimes, you just want a cool experience to share with family members or a tight group of friends. The Floating Seahorse serves up all the underwater fun without the romantic add-ons and moody lighting schemes. Keep it in mind the next time your gang wants a Kardashian-style group getaway.

1 Atlantis The Palm: Dubai, UAE

Can something be over-the-top and under the sea at the same time? That's how we'd describe the Atlantis. You cannot ask for more from an underwater hotel experience, and the world's most elite travelers know it.

There are 65,000 marine inhabitants in the resort's one-of-a-kind aquarium lagoon. You can see them interact, overcome predators, ride the currents, and check out their own reflections in the fishbowl-like windows of your hotel room. Feel like swimming yourself? Of course, the hotel has perfect pools.

But right next to the resort, you'll find the Aquaventure water park where you can release your wild side. It's also next to Nasimi Beach, which hosts world-class concerts at night when it's not playing host to sun-hungry travelers like you.

Guests who have felt the flow of the waves at the Atlantis include celebrities like Kim and Khloe Kardashian and Justin Bieber. When money is not an option and someone's looking for a unique, trendy, and ultra-relaxing hotel experience, this resort is where they come. Rub shoulders with industry elites in the resort's elegant communal spaces and then dive down into your own room at the bottom of the sea. Live the life aquatic at the ultimate fully-submerged, celebrity-approved Atlantis The Palm.

Sources: Architecturalism.com, TripAdvisor.com, Thoe.com