Candy sands, disappearing waves, transformed trolls -- if life is a beach, these are its strangest days. These 10 beaches might not all be swimmable but they are all extraordinary.

Bowling Ball Beach, California
Compared to green sand or vanishing tides, “round rocks” don’t initially sound like reason enough to visit this Californian beach. And yet, when you get down there and see the “bowling balls” sitting like some tidy giant’s game on the sand, you cannot help but get a thrill. Best seen at low tide, the rocks are freakily round and freakily regular, and clustered together as if they have been placed there. The truth is, they are stubborn. The softer rock around them washed away, but these tough customers withstood the waves.

The Bowling Balls are on the Mendocino Coast; take the Schooner Gulch Road off Highway 1.

Harbour Island, Bahamas
Are you in some kind of fairy-floss and cream-pie hallucination? Or is that sand really pink? The colour is caused by tiny particles of coral mixing in with the white sand. Pink-sand beaches occur all along the east coast of Harbour Island, sitting pretty next to the lucid, blue Bahamian seas. At the Pink Sands Resort, you can have afternoon cocktails on your private balcony while looking out onto the petal-coloured sands. Leave the rose-coloured glasses at home.

Glass Beach, California
This beach is a testament to nature’s amazing ability to turn trash into treasure. Overlooked by cliffs, it was once seen as just a convenient dumping ground for Fort Braggs’ garbage. Up until the late 1960s people would hurl their refuse – including old cars and appliances – straight over the cliffs and into the ocean. Finally the authorities put a stop to it. Over the ensuing decades, the sea performed a remarkable conjuring act, acting like a huge tumbler to winnow out the glass and turn it smooth. These days the beach resembles a gem shop. People used to collect the glass, but that is now forbidden.

To get there, follow Fort Bragg’s Elm Street to its end and then hike down the dirt trail to the beach. Take care, the path can be treacherous.

Prince William Sound, Alaska
Close to the northernmost point of the Gulf of Alaska, beaches get truly otherworldly. Tidewater glaciers spill into the sea, the air is cold and clear, mountain peaks reflect in the pure water and black sand is framed by green hills and blue ice. Then you see the region’s wildlife – harbour seals, sea otters, whales, eagles and bears to name but a few. It is no wonder Prince William Sound is heaven for kayakers. Alternatively, consider a glacier cruise.

Papakolea, Hawaii
When it comes to beaches, the volcanic islands of Hawaii are not content to leave it at sugar-white. They mix it up with ebony black, Mars red – and green! Papakōlea is not exactly blazing emerald, but it does have a distinct green tint from olivine crystals deposited on the beach by a volcanic explosion about 10,000 years ago. These crystals are heavier than the other volcanic materials, so as the water washes the rest away, the beach gets greener. Eventually the olivine will run out and the beach will be grey, but not any time soon in human terms.

Papakōlea is in the Ka‘u district of Hawaii’s Big Island. You will have to hike in and climb down the cinder cone.

Chandipur, India
The sea here has a magic trick – it disappears! At low tide it waves goodbye and heads out for around five kilometres. That in itself may not be enough to draw you here, but while you are waiting for the sea to come sloshing back in, you will be able to explore the seabed, complete with shells, driftwood and little red crabs. And when you are in Orissa, why not check out some of its other off-the-tourist-trail beaches? Visit the Orissan town of Puri in June or July for the stunning Rath Yatra festival.

Perissa, Greece
Do not expect to get this one to yourself – with a beach this famous, you have to share. Perissa is probably the most beautiful of Santorini’s black-sand beaches, overlooked by the huge rock Mesa Vouno, which is lit up at night. The beach is long so you will not be too squashed by the hordes, but if you do feel like some time out, the ruins of Thira, an ancient city, are just a sprightly hike away. Bring flip-flops to this beach as the black sand holds the heat.

Stay close to the action at Stelios Place, just metres from the beach; it has white balconies, a pool and good breakfasts.

Giant’s Causeway, Northern Ireland
It is easy to see how legends grew up around the Giant’s Causeway. Volcanic eruption has shaped thousands of basalt columns into precise hexagonal shapes, grouped together like organ pipes. It is almost impossible to believe that they have not been carved by human hands. The mythology of the place has the famed warrior Finn McCool swapping shouted threats with a Scottish giant over the sea. They started to make a causeway so they could get their hands on each other. (Geology supports the myth: there are similar structures on the Scottish side of the sea.) Do not miss particularly sculptural structures like the Giant’s Boot and the Chimney Stacks.

Rainbow Beach, Australia
Not content with merely taking on an unusual colour, Rainbow Beach takes on a myriad. On Fraser Island (the world’s largest sand island) off Australia’s east coast, the beach is backed by exquisite cliffs where you can see the rainbow colours most clearly in edible-looking striations of nougat, rose, honey and cream. Aboriginal legend has it that a spirit personified in the rainbow dove into the cliffs during a fight over a woman, staining them with his colours. The sand looks gold from a distance, but scoop up a handful and you will see the rainbow.

Get up early to hand-feed wild dolphins at nearby Tin Can Bay. There is only one feeding a day, at 8am sharp.

Vík Beach, Iceland
The little town of Vík has three distinctions. One, it is Iceland’s southernmost point. Two, it is the rainiest place on the island. And three, it has one of the most beautiful beaches in the world. White waves wash up on jet-black sands, like a beach seen in negative. The cliffs above glow green from all that rain. And strange basalt figures, traditionally believed to be ill-fated trolls that got caught out in the sun, stand here and there like sculptures.

The article 'The world’s most unusual beaches' was published in partnership with Lonely Planet.