16 of the most alien-looking beaches on Earth

Koekohe Beach, located on New Zealand's Otago coast, is characterized by its unusual stone-like formations. In reality, the otherworldly Moeraki Boulders — which could pass for dragon's eggs or alien cocoons — are concretions, or compact masses of mineral matter. 

Dating back a whooping 60 million years, the boulders began forming in sea floor sediments. The heaviest ones weigh multiple tons. 

Minuscule lava fragments are the reason why Hawaii's Punalu'u Beach has black sand instead of the expected tan variety.

In addition to its dark color, the beach is also known for the turtles (endangered hawksbills and green turtles) who can be found lounging there. 

Vík, Iceland, is famous for two things — its black beach and sinister-looking rock formations.

Like Punalu'u, Vík's Reynisfjara Beach has black sand. The village is also known for the trio of dramatic basalt rock formations (Reynisdrangar) that jut out from the North Atlantic Ocean.

In Icelandic folklore, the three rocks are actually trolls who were frozen in the sunlight after attempting to pull a ship from the sea overnight. 

One of the most famous locales in Northern Ireland is the Giant's Causeway. Forty thousand black basalt columns comprise the site, which was formed by volcanic activity 50 to 60 million years ago. 

According to legend, the breathtaking stacks of five- and seven-sided stones resulted from the battle between the hunter-warrior Fionn mac Cumhaill (or McCool) and the Scottish giant Benandonner. 

A former garbage dump site, Glass Beach in Fort Bragg, California, proves that one person's trash is another person's treasure.

Between 1906 and 1967, Fort Bragg residents commonly dumped their detritus into the ocean by shoving it off the city's cliffs. Over the years, the ebb and flow of the tide turned the debris from abandoned cars, used appliances, and other refuse into beautiful sea glass.

One of the rarest finds is ruby red glass from pre-1967 car tail lights. 

You might mistake Red Sand Beach, located on the Galápagos archipelago's Rábida Island, for the surface of Mars. The rusty color comes from the high concentration of iron in the island's volcanic material. 

Although it has no human population, Rábida is home to a diverse array of wildlife, ranging from the famous Galápagos sea turtle to sea lions and eagle rays. 

In India, you'll find Chandipur Beach, nicknamed "vanishing beach" or "hide-and-seek beach" because of the way in which the sea water recedes up to three miles during low tide — a phenomenon that occurs twice daily.

Amazingly, you can walk right into the empty seabed, where you'll see discarded seashells and small fish swimming in puddles.

Located on the Croatian isle of Brač — the tallest island in the Adriatic — Zlatni Rat (Golden Horn) is remarkable for its white pebbles.

Astonishingly, the tip of the cone-shaped beach, which extends more than 1600 feet into the sea, changes shape depending on the direction of the wind.

The Greek islands' picturesque beaches are a major draw for tourists. Xi Beach, one of the country's most unique, astounds visitors with its juxtaposition of red sand and white cliffs.

Xi, located on the isle of Kefalonia, is named for a nearby, x-shaped cove. 

About three hours from Sydney, Hyams Beach — which sits on the shore of Australia's Jervis Bay — boasts some of the lightest-colored sand on the planet.

In fact, Guinness World Records has designated Hyams' granules the world's whitest. 

At first glance, you might assume that an architect had something to do with the buttress-like formations at the Beach of the Cathedrals in Spain's Galicia region. But these rocky arches were formed by nature alone. 

In the Galician language, the area is known as Praia de Augas Santas (Beach of the Holy Waters). 

You can witness Maldives' extraordinary glowing beaches on many of the country's 1,190  islands. Some of the best spots to view this natural marvel — for which we can thank bioluminescent plankton — are on the shores of Athuruga, Reethi, and Mirihi.

These incredible glow-in-the-dark creatures create light with the chemical luciferin (the same compound that allows fireflies to emit light). Outside of Maldives, the plankton can be found in other locations around the world including Puerto Rico, Australia, and even New Jersey. 

Contrary to what you might think, the name of Okinawa Prefecture's Hoshizuna no Hama (Star Sand Beach) — which is located on a remote island in southwestern Japan — is not figurative.

The beach's sand is comprised of the star-shaped exoskeletons of tiny organisms called protists.

If you wonder what it would be like to take a vacation to Jurassic Park, look no further than England's Jurassic Coast, which spans 95 miles from East Devon to Dorset.

The coast's cliffs — the oldest of which date back 240 million years — have yielded vital archaeological finds, including the bones of early amphibians, land reptiles, and (of course) dinosaurs.

From far away, Mexico's Hidden Beach — also known as Playa del Amor (Lovers' Beach)  — appears to be nothing more than a gaping hole. But the gap is actually the opening to a sandy cavern on the shore of the Pacific Ocean. 

While many odd-looking beach features across the planet have occurred naturally, rumor has it that the hole was created when Mexico began using the Marieta Islands as a military testing site in the early 1900s.

Cape Town's Boulders Beach, situated near Table Mountain, is known for its resident penguin colony.

Still, the eponymous granite formations are pretty eye-catching by themselves. 

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