The planet is full of incredible and surreal places that truly look out-of-this-world. From colourful mountains, to acidic volcanoes and underwater sinkholes, check out these unbelievable destinations.

The dramatic Tianzi Mountains are located at the Zhangjiajie National Forest Park in the Hunan Province of China. Informally known as the 'Avatar Mountains', the sandstone pillars provided the inspiration for the alien landscape in the 2009 animated film.

One of Turkey’s most-visited sites, the surreal travertine terraces of Pamukkale (meaning 'cotton castle') are a geological phenomenon. The striking pools are a result of the mineral-rich hot springs that bubble away beneath the ground. To avoid the crowds, stay in Pamukkale Village and visit in the morning – most day-trippers don’t arrive until the afternoon.

This stunning 'underwater waterfall' is located just off the coast of Mauritius in the Indian Ocean. Its nickname is misleading, as it's no more than an optical illusion caused by sand and silt plunging down a huge underwater cliff.

One of the most active volcanoes in the world, Kīlauea in Hawaii has been erupting continuously since 1983. Over the years, its constant fiery lava flow has spread and destroyed miles of highways and hundreds of homes.

The ancient red city of Petra, located in the deserts of Jordan, is one of the world’s largest and most important archaeological sites. Inhabited since prehistoric times, this otherworldly empire was half-built and half-carved into the rocks. In 2007, it was voted one the 'New7Wonders of the World'.

No one really knows why a grove of 400 pine trees in Poland have grown with the same mysterious bends. The Krzywy Las, or Crooked Forest, was planted in the 1930s and it’s thought they may have been stunted by a snowstorm. Legend also has it that a group of farmers manipulated them, hoping to make furniture when they reached 10 years of age – but, the plans were abandoned following the start of WWII.

Thousands of these limestone rocks, some of which stand at around 16 feet tall, can be found at Nambung National Park, Western Australia. It’s thought the pillars formed 25,000 to 30,000 years ago, after the sea receded and coastal winds eroded the surrounding sands.

Also known as the Devil’s Bath, Wai-O-Tapu in New Zealand is a geothermal wonderland of hot springs, stagnant sulphur lakes, mud pools, a waterfall and the Lady Knox geyser. Sculpted over thousands of years thanks to volcanic activity, the name Wai-O-Tapu is Māori for 'sacred waters'.

Known as The Door To Hell, this fiery basin of Derweze, Turkmenistan, has been flaming for more than 40 years. The 230-foot-wide crater was created when a Soviet drilling rig collapsed in 1971, releasing huge quantities of methane gas. It has been burning ever since. In April 2010 the country's president, Gurbanguly Berdimuhamedow ordered that the hole should be closed – but it hasn’t happened yet.

Haleakalā National Park in Maui, Hawaii, offers out-of-this-world landscapes and spectacular sunrises. One side of the park, known as the Kipahulu area, is full of lush green foliage, while the Summit area (pictured) has a jagged moon-like surface. Here you'll find the Haleakalā volcano, which overlooks an enormous 10,498-foot-wide crater.

The stunning rainbow landscape of the Zhangye Danxia mountains, dubbed 'the eye candy of Zhangye' by locals, is located in Gansu, China. Geologists believe the colourful layers of red sandstone and other mineral deposits built on top of each other over millions of years before a dramatic tectonic shift caused the mountains to form.

Towering above the clouds, the majestic Mount Roraima is a natural border between Venezuela, Brazil and Guyana in South America. At around two billion years old, the mountains are considered to be some of the oldest in the world and peak at around 9,094 feet high.

Despite looking like alien life forms, these striking specks of neon-blue light appear naturally along the beaches in the Maldives. The phenomenon occurs as bio luminescent bacteria emit a bright light when stressed or disturbed to surprise predators.

Nicknamed 'the Palace of Natural Arts', the Reed Flute Cave in Gullin, China, is a 787-foot-deep cavern of creatively illuminated neon stalactites, stalagmites, stone pillars and plants. The ancient cave was discovered by a group of exiles fleeing Japanese forces during the 1940s, who found ink inscriptions dating back to AD 792 Tang Dynasty.

The Dallol Volcano is the lowest point in Africa, measuring 157 feet below sea level. The craters contain hot springs of neon-yellow and greens, created by the hot magma bubbling below. The volcano hasn’t erupted since 1926, but visitors should be more wary of the dangers posed by the hot acid waters and rancid toxic gases in the area.

Star Wars fans will instantly recognise Tataouine, deep within the Tunisian desert, as the inspiration for Luke Skywalker’s sandy home planet of Tatooine in the blockbuster movies. Unsurprisingly, the ancient village became popular with film fans, though visitor numbers have dwindled in recent years due to conflict in the area.

Stretching across an immense 4,086 square miles, the Salar De Uyuni is the world’s largest salt flat – and a breathtaking natural mirror. The surface becomes reflective when water floods the plane, making it look as though visitors are walking in the clouds. The dream-like destination is located in Potosí, southwest Bolivia, near the crest of the Andes.

The valleys of Antelope Canyon in Arizona were created over thousands of years by flash flooding, which eroded the sandstone pathways and shaped the distinctive curves you see today. A photographer’s dream, thanks to the ever-changing shadows and colours, the canyon can only be visited as part of an organised tour.

The Great Blue Hole is the world’s largest submarine sinkhole, measuring 1,043 feet across and 407 feet deep. Located 43 miles off the coast of Belize, the crater is a popular site with divers.

These pastel-coloured Painted Dunes are a highlight of Lassen National Park in California. Sitting in the shadows of the Cinder Cone volcano, the otherworldly red and orange mounds are formed of oxidised volcanic ash layers and dotted with pine trees.

The world’s largest pool of freshwater, Lake Baikal has a surface area larger than Belgium and contains a fifth of the Earth’s fresh water. From early January until around May or June, the lake completely freezes over, creating layers of ice that are up to five foot deep.

The aptly-named Valle de la Luna, or Moon Valley, is located in Chile’s Atacama Desert – one of the driest in the world. The dramatic landscape is filled with craggy peaks, craters and deep layers of rock salt. The area is most popular in the evenings, when tourists flock to watch the incredible sunsets.

Vatnajökull is the largest glacier in Europe, covering 3,100 square miles of Iceland – about 8% of the island. Thought to have formed over thousands of years, the ice cap sits above three volcanoes. It's possible to go hiking inside the incredible electric blue 'crystal caves' during the winter months.

Often referred to as the 'alien island', Socotra is located off the coast of Yemen. Around 800 species of plants and flowers exist here, a third of which can be found nowhere else on Earth. This unusual Dragon’s blood tree (pictured) is so called because it produces bright red sap.

These scorched tree skeletons can found among the red dunes of the Namib Desert. One of the largest and oldest deserts in the world, the Namib spans over 31,200 square miles and is thought to be around 43 million years old.

The magnificent Torri del Vajolet, or 'Vajolet Towers', are located in the Dolomites mountain range in northeastern Italy. These famous towers are the most photographed peaks in the region and considered a bucket list location for rock climbers.

Also known as Kliluk, the Spotted Lake is located between the Okanagan and Similkameen Valleys in the British Columbia desert. As the water evaporates during the summer, it leaves behind around 300 colourful salt crystal polka dots. The lake is considered a sacred place by Canada’s First Nations people, who believe each circle holds different healing properties.

The Giant's Causeway is a collection of 40,000 basalt columns. Northern Ireland's first UNESCO World Heritage Site, geologists believe it was created by a volcanic eruption 60 million years ago. However, according to local myth the path was built by legendary giant Finn MacCool so he could walk across the North Channel.

These striking rocks rise out of the water along the shore of the Mono Lake in California. The jagged limestones, known as tufa, are created during a chemical reaction between the calcium-rich underwater springs and the carbonates in the lake water above.

Zion National Park in Utah is a vast wilderness of steep sandstone cliffs, narrow canyons, dramatic waterfalls and sweeping deserts. One of the park's most popular hikes is the challenging four-hour trip to the summit of Angels Landing, a 1,400-foot peak which offers breathtaking views.