Throughout the history of mankind, we have gone from caves to huts, from castles to apartment blocks. And these days, it seems that we can see every possible design of buildings all over the world. The architects who designed them were guided by different things. Some of them drew inspiration from nature and tried to make their buildings look like they were created naturally, without the efforts made by human hands. Others faced different kinds of restrictions and had to fit their house into specific surroundings, limited by size or an unusual location. And there also were those, who just wanted to create something new that would look different from everything else in this world. But there is one thing that unites them all: all these designs made a statement in the world of architecture.

From the houses that seem to perfectly blend with the natural setting surrounding them, to the constructions made of the most unexpected materials, to the buildings that look like they came right off the pages of fairy tales, this list allows you to have an overview of the most unusual architect designs that exist all over the world. While checking them out, imagine yourself living in each one of these houses and then share with us in the comment section, which design you'd like to have as your own "home, sweet home"!

20 Flintstones Inspired Home, Malibu, California

This house that looks totally like the house of the Flintstones used to belong to a TV and radio legend Dick Clark, who reportedly sold it for $3.5million. But the outside appearance of the house isn't the only thing that attracts attention to it. It looks awesome on the inside, as well.

The Flintstones' home has one bedroom and two bathrooms, as well as a fireplace and several large windows that offer the 360-degree views of the Pacific Ocean and the Channel Islands. To match the exterior, the house's interior also looks like the inside of a cave, which gives it a special charm.

19 The Keret House, Warsaw, Poland

Measuring only 122 centimeters (48 inches) at its widest point, this unusual structure is considered to be the skinniest house in the world. You can see it in Warsaw, Poland, but look carefully. You can easily miss it because this narrow house is squeezed between two more conventional buildings.

Architect Jakub Szczesny, the creator of the house, got the idea to build it about 10 years ago and presented it at the WolaArt festival in 2009. Three years after it, he materialized his idea and proved that it was possible to make sure that no urban spaces go unused.

The house's interior is white and it's semi-transparent, so you aren't likely to feel claustrophobic in it.

18 Giant Seashell House, Mexico City, Mexico

The architect of this house drew inspiration from the works of Antoni Gaudi and Frank Lloyd Wright to create this house that looks like a giant seashell. The exterior of the house has multiple colored glass pieces that make it sparkle in the sunny weather. And if you come to this house, you're likely to be amazed even more.

Nothing in the house's interior has right angles. Instead, everything is rounded, which gives a very smooth and relaxing look to the interior. Windows, tables, chairs, and even the beds and couches in the house are round.

It must be such a special place to live in!

17 Upside Down House, Trassenheide, Germany

Unlike most other houses in this list, this one wasn't built for people to live in it. Polish architects Klaudiusz Golos and Sebastian Mikiciuk designed and constructed it as a tourist attraction in Trassenheide, Germany. It was part of a very curious 'World Upside Down Project' that certainly did its job, making visitors amazed.

But the outside of the house isn't the only upside-down thing. Everything inside of it, including the furniture, is also turned upside-down! Doesn't this kind of interior let people see the world from a different perspective? Well, of course, walking into this house can be kind of disorienting, but still...

16 The Toilet House, Suwon, South Korea

This house doesn't only look unusual, but it also has an interesting story behind its creation. First of all, it was designed by the Mayor of Suwon Sim Jae-Duk. Secondly, this one-of-a-kind construction is supposed to commemorate the founding of the World Toilet Association. And thirdly, yes, this is a real organization, not a figment of the mayor's imagination.

The rooftop of the house features a series of flags of different countries. If you look closer at them, you might test your knowledge and guess some of the flags and, you know, perhaps even forget that they're situated on the rim of a giant toilet.

15 The Mushroom House, Cincinnati, Ohio

Have you ever wanted to live inside a mushroom? Then this house is your dream! Designed by architecture professor Terry Brown, the Mushroom House has a lot of warped shingles and oddly wrapping staircases that give it a magical view and make you feel like you got into a fairy tale. The bulbous roofing of the house completes its fungal look, while oval-shaped windows animate the giant mushroom and make it look like it's watching you. And there is also a glass-walled sunroom jutting out on one end of the construction that gives it a bit less organic, but, somehow, even more thrilling appearance.

14 Streamline Home, Inverloch, Australia

Looks like a spacecraft parked near a lake for the aliens to take a dip after a long and exhausting flight, right? But, in fact, it's just a house in Inverloch, Australia!

Designed by Australian architect James Stockwell, this house gorgeously accompanies the beautiful seaside vistas due to its low lying design, as well as its exterior inspired by nature and conformity with the scenic landscape. Besides, the house also allows its residents to leave minimal carbon footprint because it has solar panels, compressed sand walls that create the optimal temperature inside, and huge windows that give maximum natural light. Besides, it was constructed with locally sourced materials!

13 Transparent House, Tokyo, Japan

Are you tired of living behind four walls that block the outside world for you? Would you like to live in a house, where walls aren't limiting you from seeing the world around? Then, perhaps, you're going to like the Transparent House in Tokyo (especially if you couldn't care less about privacy)!

Interestingly, this house's design was inspired by our ancestors living on the trees. "The intriguing point of a tree is that these places are not hermetically isolated but are connected to one another in its unique relativity. To hear one’s voice from across and above, hopping over to another branch, a discussion taking place across branches by members from separate branches. These are some of the moments of richness encountered through such spatially dense living," says Sou Fujimoto, the house's designer.

12 The Tree Hotel, Harads, Sweden

If you aren't only tired of enclosed space, but also can't stand living in the big city any longer, then think about this unique tree house in Sweden designed by Tham & Videgård Arkitekter. Well, technically, it's not a home, but a Tree Hotel that offers a 360-degree view over the surrounding landscape.

This cube-shaped structure is wrapped around the trunk of a tree, but this shouldn't make you worry. The tree doesn't suffer from it, because the construction is made of aluminum, a very lightweight material. And since the exterior is clad in mirrored glass, the structure perfectly blends in with the surrounding area. From a certain angle, you might think that it's not even there...

11 The Kvivik Igloos, Kvivik, Faroe Islands

The Faroe Islands are beautiful. But this geodesic, grass-roofed igloo is even more beautiful, isn't it? And there is not one, not two, but a whole village of similar igloos in Kvivik. You can guess that they're offered for tourists to stay in them during their vacation on the Faroe Islands and I bet that they attract dozens of people each season!

The Kvivik Igloos are about 10 square meters in size and they are really cozy on the inside. Due to their green roofs and small wood stoves in each house, there's more than enough heat. So they're small, nice and warm, providing you with a shelter from the chilly weather. Is there anything else you could wish for?

10 The Shoe House, Hellam, Pennsylvania

One of the oldest houses in this list (excluding only Gaudi's Casa Mila), the Shoe House in Hellam, Pennsylvania was constructed in 1949. It was commissioned by shoe salesman Mahlon Haines as a way to promote his business. At some point after construction, the Shoe House was rented out to couples, but now this 5-story building is open for public tours.

According to a funny story behind the construction of this house, Haines requested this design from the architect he hired, by handing him a work boot and saying, "Build me a house like this."

A couple of words about the house's interior: the kitchen is located in the heel, the living room is in the toe, and two bedrooms are in the ankle.

9 The Bubble House, Cannes, France

People working in the creative industry are known for their eccentricity and fashion designer Pierre Cardin is no exception. In a desire to be surrounded by the designs that continuously inspire him, he purchased a Bubble House in Cannes 25 years ago.

The house was designed by architect Antti Lovag and initially it was built for a French businessman, but, unfortunately, the latter passed away midway through construction. So Cardin found the house right in time and the complete works were performed for him. Knowing the personality and avant-garde works by Pierre Cardin, we can certainly guess that the house's interior looks as extraordinary as its exterior!

8 The Pole House, Fairhaven, Australia

This house, overlooking the Great Ocean Road in Australia was designed and built by F2 Architecture. It's interesting that the architects decided to take advantage of the house's location in an extraordinary way. First of all, it was constructed on a steep hillside, where it seemed to be impossible to build a massive structure. The architects fulfilled this challenge successfully, due to their idea to construct a concrete platform on a 13-meter-high pole and place the house on it!

This led to the second challenge: the uneasy access to the house. But this issue was solved, as well, by building a narrow concrete bridge to link the house and the hillside. Genius, right?

7 Dr. Seuss House, Willow, Alaska

It seems that the design of this unusual house came right from the pages of a fairy tale or a fiction book. According to the story behind the so-called Dr. Seuss House, its first owner liked to live in it, because he had a clear view of Mount McKinley and Denali National Park from the windows. But, as the trees around the house grew and obscured the view, he had to build more and more new stories to keep on enjoying the landscapes. Little by little, he made 12 stories but eventually left the house.

The current owner is reportedly working on renovating the house, so we'll see how it'll look in the future.

6 Gue(ho)st House, Delme, France

Few other houses have such a haunting appearance as this one. This eerie design was created by French artists Christophe Berdaguer and Marie Péjus, who converted an old house, that used to be a prison house, a school, and a funeral home, into a visitor center of a contemporary art center in Delme. To create this ghostly appearance and give chunky shapes to the facade, the designers used blocks of polystyrene and covered them with resin and white paint.

The artists named it the Gue(ho)st House, referring to the famous phrase by Marcel Duchamp "A GUEST + A HOST = A GHOST". Huh, what an interesting analogy...

5 The Steel House, Lubbock, Texas

This house looks more like a giant work of art that should be exhibited at a contemporary art gallery. Its story began back in 1973 when sculptor Robert Bruno known for his unconventional works began this project. He had been tirelessly working on this house up until the year 2008 when he passed away.

Everything in this house was handcrafted by Bruno, without the use of any outside help. And, even though the house hasn't been completed, it attracts a number of visitors, who find something interesting for themselves in it. Some think it looks like an alien spaceship, for others it resembles a Star Wars AT-AT Walker, and there're also those, who compare it to a giant pig or even an insect.

4 Stone House, Portugal

We had the Steel House, the Glass House, and now here's the Stone House! Yes, it's literally made of stone! And it is a real wonder that you can find in the majestic countryside of Portugal. It isn't hard to guess that the construction of this house was inspired by the Flintstones, even though, compared to the Flintstones Home we saw earlier, it doesn't look as much as the house from the animated movie.

Both the exterior and interior of the Stone House are very simple and the design is very minimal. But, at the same time, this construction makes a strong architectural statement. Simplicity is genius, after all.

3 Mirror Home, Almere, The Netherlands

If you'd like your house to camouflage with the surroundings, this design will look perfect for you. This house was designed by Swedish architect Johan Selbing and Swiss landscape architect Anouk Vogel. All of its walls are covered in reflective glass allowing it to blend with the landscape. If you look at this house from a certain angle, you'll even realize that you can't see it!

The house is built from an aluminum frame and the panels of toughened mirrored glass that cover the entire facade of the house, including its roof. The interior is designed keeping minimalism and simplicity in mind - there are a home office, bedrooms, an open-plan kitchen and living space divided by sliding partitions.

2 Casa Mila, Barcelona, Spain (The First Of The First)

I can't help but include in this list the most extraordinary architect that ever lived on this planet. Obviously, I'm talking about Antoni Gaudi, a famous Spanish architect from Catalonia. His works that feature the unique style never seen before can be found all over Barcelona. They include the renowned Sagrada Familia, a cathedral that's being built for over 130 years now, a Casa Mila that you can see in the photo above.

Aka La Pedrera ("the stone quarry"), Casa Mila caused a stir in the architectural society of the 19th century, because its design looked nothing like common buildings of those days. Resembling a rock quarry, it was highly inspired by nature. To these days, Casa Mila attracts the attention of both professional architects and the average men. It's not surprising why - I mean, just look at it!

1 The Cloud House, Melbourne, Australia

Designed by McBride Charles Ryan, this house is likely to make you feel like you're on the Cloud 9. The one-of-a-kind design of the Cloud House is incredibly attractive. It has a large area created especially for family activities and relaxation. Its glass exterior walls have an unobstructed panoramic view of the surrounding landscape, allowing to gaze at nature outside without leaving the house. And the curved lines of the house's roof give a futuristic look that will impress anyone who either enters the house or just sees it in photos.

So would you like to live in any of these houses?

References: Independent Travel Cats, Daily Mail, Homedit, Scoop Whoop, The House Shop, Atlas Obscura, Inhabitat, Bored Panda, Smith Journal, This Is Colossal, De Zeen