Deserts are hostile and lonely places. Vast plains of sand stretching as far as the eye can see, and a hostile climate, make these huge swathes of land mysterious and fascinating.

Deserts cover approximately one-third of the Earth's land surface, according to the US Geological Survey, but there’s often more to these extreme environments than just insane quantities of sand. They are home to some of the most bizarre flora and fauna on the planet, not to mention the weird and wonderful secrets buried beneath their surface.

From long-forgotten cities, ancient monuments to ambitious artworks and, erm, a stash of retro video games, deserts are the keepers of civilisations’ secrets, some of which may never be unearthed.

Some of their hidden secrets, however, have been discovered thanks to archeologists getting their hands dirty, a bit of pure chance, or the technological marvel that is Google Earth.

Here, to excite your inner Indiana Jones, we’ve gathered together pictures of 25 of the weirdest things discovered in deserts around the world.

25 11. A Giant Stone Hand In Chile

Situated in the Atacama desert in Chile, along the Pan-American Highway, an enormous hand rises 36 feet out of the sand. It looks like something from Game of Thrones, but La Mano del Desierto, ”the Hand of the Desert,” was commissioned by the isolated city of Antofagasta more than 25 years ago. The hand is the work of Santiago sculptor Mario Mario Irarrázabal, and it’s a monument dedicated to the emptiness of its Atacama Desert location, and symbolises human vulnerability.

It's a frequent target for vandals, according to Condé Nast Traveler, but twice a year, volunteers from the city scrub the sculpture clean.

24 1. The Ghost Town Of Namib Desert

Once home to hundreds of German families, the town of Kolmanskop was founded in Namibian Desert after the discovery of diamonds in 1908.

People flocked to the area and built a grand town with European architecture, stately homes, a hospital, casino and theatre, but by 1954, diamond mining had ceased and the town was left to the mercy of the desert.

Kolmanskop is still standing, although it’s an eery shadow of its former glorious incarnation, and is now a popular spot for tourists.

23 15. Just Some Upside Down Cadillacs

The product of an eccentric millionaire and San Francisco art collective The Ant Farm, Cadillac Ranch is an installation in a dusty Texas cow pasture, along eastbound I-40, between exits 60 and 62.

The artwork consists of 10 cars half-buried, nose-down, and facing west “at the same angle as the Cheops’ pyramids,” according to Atlas Obscura. The Cadillacs are completely covered in graffiti and visitors are encouraged to add their own designs.

22 17. The "Desert Breath" Art Installation

This precise and beautiful arrangement of cone shapes, in between the Red Sea and a mountain range in Egypt’s Eastern Desert region, has had Google Maps fanatics in a whirl. Its explanation, however, couldn’t be simpler. It’s an art installation called Desert Breath, and it was finished in 1997.

The work, by D.A.S.T. Arteam, is epic in scale and took two years complete, with more than 8,000 cubic metres of sand displaced across 100,000-square-metres of desert.

21 14. Fairy Circles In The Namib Desert

In the Namib Desert, in the country of Namibia, evenly spaced, concentric circles in the middle of vegetation have sparked the curiosity of scientists for years. Fires, winds and aliens have all be floated as the cause for these peculiar patterns, and the real explanation is still unknown.

According to New Scientist, however, two theories stand out as the likely frontrunners. One claims the empty patches, known as fairy circles, are created by termites clearing vegetation in the area around their nests to create underground reservoirs of water. The other leading idea is that the circles are caused by plants competing for water.

Neither of these fully explain why the circles remain barren for so long with no visible trace of colonies. The mystery continues.

20 25. A Fake Prada Store In The Texas Desert

Of all the places you’d expect to find a Prada boutique, the lone stretch of land along US 90, 26 miles outside the town of Marfa in Texas, isn’t one of them. But in 2005, Berlin-based artists Elmgreen and Dragset built one - well, a fake one - as an art installation.

It might not be a real shop, but it did contain real Prada merchandise, before it was robbed and vandalised just days after opening.

Built out of a biodegradable substance, the building is designed to slowly decay back into the Earth, acting as kind of a surrealist commentary on Western materialism, according to Vogue.

19 24. Mysterious Patterns In The Gobi Desert, China

In 2011, Google Earth users found a bizarre collection of white lines carved into the Gobi Desert areas of China’s Xinjiang and Gansu provinces. The unidentified shapes, which include blocks of silver squares and concentric circles, sent the internet into meltdown, with theorists speculating they could be anything from satellite-weapon targets to messages to, or even from, aliens.

But Jonathon Hill, a research technician at the Mars Space Flight Facility at Arizona State University, told LiveScience that the weird zig-zag shapes were most likely to be Chinese satellite calibration targets. We like the alien theory more.

18 23. Ballistic Missiles Leftover From The Cold War

Near Tuscon, Arizona, is the Titan Missile Museum, a national monument that preserves complex 571-7, the only remaining Titan II missile site out of 54, that were once on alert across the US from 1963 to 1987.

Once a top-secret location, the site is now open to the public, who can enjoy guided tours of the control room, experience a simulated missile launch, and head 200ft underground to see the Titan II missile up close. No need to worry, it’s been long decommissioned.

17 22. The 60-Ft Buried Boat That Baffled Archeologists

For ancient Egyptian royalty, it was common to be buried with some kind of vehicle, including boats. But in 2016, Czech archeologists uncovered an ancient funerary boat that left them baffled, according to the Smithsonian Magazine.

The 62-foot-long boat, dating back more than 4,500 years, was found in a tomb made of mud bricks. Not only was it amazingly well preserved, with its high-quality wood still intact, but it was located nowhere near a royal burial ground, raising the possibility it was buried with a commoner. But how could they have afforded it? How could they have transported it inland? It certainly raised more questions than it answered.

16 21. Giant Concrete Arrows In Arizona

In the Arizona desert, and dotted throughout the US, are enormous concrete arrows. The structures were built in the late 1920s and early 1930s by the Air Traffic Control Association, according to CNN Travel. Measuring up to 70ft in length, the arrows were placed at the base of lit beacons, which were used to help mail pilots with navigation, long before satellites and GPS.

While most of the light towers are long gone, the arrows lie abandoned, waiting to be discovered by walkers, or by eagle-eyed enthusiasts studying Google's aerial maps.

15 20. A Desert Graveyard For Sea Mammals

In Chile’s Atacama Desert there’s a hill called Cerro Ballena, “Whale Hill,” which has long been known as a fossil bed for whales, thanks to the visible bones sticking out of the rocks. It was only during roadworks on the Pan-Am Highway in 2014, however, that researchers were allowed access to properly examine the site.

According to the BBC, scientists now have a theory as to how so many of the animals ended up in this location more than five million years ago. The evidence suggests it was a result of four mass strandings due to ingesting toxic algae. The creatures were then washed into an estuary, where they became buried with sand over millennia.

14 19. The Tunisian Lake That Sprung From Nowhere

In 2014, shepherds in Tunisia happened upon a lake that had seemingly appeared out of nowhere. It was no small body of water, either, covering an estimated one hectare and up to 18 metres deep, according to The Guardian.

Lac de Gafsa, as it was christened, became a buzzing hang-out spot for locals, who delighted in the opportunity to cool off in the baking heat, despite warnings it could be contaminated, even potentially radioactive.

The area is known for its phosphate mine and, claimed local seismologists, the lake potentially came from an underwater spring freed by the mining process. Locals, however, were undeterred, despite the water turning green.

13 18. The Phone Booth In The Mojave Desert

The Mojave phone booth was first installed in 1948 to service the local volcanic cinder miners. By 1997, however, it became an internet obsession and something of an icon, with people around the world calling the booth in the hope someone might answer, and visitors camping beside it just for the chance to pick up a random call.

According to Slate, the booth rose to prominence after an LA resident spotted a telephone icon on a map and, intrigued by its remote location, decided to visit. He wrote about his adventure, included the booth's telephone number, and piqued the interest of others. An Arizona man, Godfrey Daniels, started a website devoted to the booth, it featured in the New York Times, and its reputation took off.

Its popularity was its downfall, however, and it was removed in 2000 because of visitors' environmental impact on the surrounding national preserve.

12 16. Yabba Dabba Doo! Bedrock City In Arizona

An amusement park and RV site inspired by Bedrock City from The Flintstones sounds like a fun idea, right? Unfortunately, despite its awesome premise, the reality of this Arizona attraction was just a little bit grim. The barren desert landscape combined with concrete ‘prehistoric homes,’ and tatty, misshapen statues of Fred and the gang, amounted to an odd and slightly post-apocalyptic vibe.

The park opened in 1972 and became a cult roadside attraction until it finally closed in 2015.

11 13. The Mansion Of Death Valley

Known as Scotty’s Castle, this opulent Spanish Colonial Revival style villa is not a real castle, and nor does it belong to anyone called Scotty. It was, in fact, built by Chicago insurance broker Albert Johnson, who was lured to Death Valley to invest in the fraudulent scheme of con man Walter Scott, known as “Death Valley Scotty”.

The two unexpectedly became friends, according to Atlas Obscura, and with the encouragement of his wife, Johnson began construction on an ambitious holiday home in 1922, investing $1.4 million dollars into the project. Once the Wall Street Crash of 1929 hit, the project went bust and the mansion was never completed.

It eventually came under the ownership of the National Park Service, which offered guided tours until a flash flood caused damage in 2015. The property will be open to visitors again in 2020.

10 12. The Works Of Old Men

Located in Jordan's Azraq Oasis, these crazy structures were first observed from the air by British pilot Percy Maitland in 1927. These “Works of the Old Men,” as Bedouins call them, are hundreds of wheel structures more than 80ft wide and some of them date back some 8,500 years.

They are thought to have astronomical significance, built to align with the sunrise on the winter solstice, but as for their purpose? No one is quite sure.

9 10. A Massive Stash Of Vintage Video Games

For more than three decades, rumours circulated that games manufacturer Atari, which was massive in the 1980s, had buried millions of copies of the now infamous game "ET: The Extra-Terrestrial.”

The game was released in 1982 and became known as the worst video game in history. Despite poor reviews, it initially sold well but according to The Independent, Atari failed to shift between 2.5 million and 3.5 million cartridges, and had produced more copies of the game then there were Atari consoles to play it on. Oops.

The rumour was confirmed in 2014 when documentary filmmakers discovered the buried cache in a landfill site in New Mexico.

8 9. A Hidden Swimming Pool In The Mojave Desert

This little man-made oasis was just 11ft by 5ft and hidden in a secret location in the Mojave Desert, until its closure in 2014.

Known as Social Pool, it was built by Austrian-born artist Alfredo Barsuglia and was open to anyone to use. The only catch was, you had to find it first.

Interested parties first had to go to the MAK Center for Art and Architecture in West Hollywood to ask for one of four keys that accessed the pool, as well as GPS coordinates. There were strict rules for using it: don’t copy the key, return it within 24 hours, and replenish the pool with a gallon of fresh water.

7 8. The Abandoned Domes Of Casa Grande

These flying saucer-shaped structures were built in the late 1970s and early 1980s as facilities to manufacturer computers, but were never completed. They’ve since fallen into wrack and ruin and, despite signs forbidding trespassing, have caught the imagination of Casa Grande locals.

According to Atlas Obscura, rumour is that the domes have been used for witchcraft and satanic worship, especially the tunnels that run beneath the east of the facility. Ghost stories aside, no trespassing is probably good advice.

6 7. Where Half Of The Residents Live Underground: Coober Pedy, Australia

Coober Pedy is the world’s largest opal mining area , but when prospectors discovered the region’s hidden treasure back in 1915, there was a practical problem. The area is seriously hot - temperatures can be 113 degrees in the shade, according to Smithsonian Magazine.

Using mining tools, early settlers solved this problem by digging holes into the hillsides to make underground homes. Today, about half of the population still live in these dugouts where the temperature remains cool, and the subterranean network includes public bars and a hotel, as well as underground homes.

In 1985, the town hit the big screen when it was used as a filming location for Mad Max Beyond Thunderdome.