Son Doong Cave, Vietnam
The world’s largest cave, able to comfortably fit a 747 plane, the Son Doong Cave was only discovered in 2009. It was, however, created more than 2.5 million years ago, formed by river water eroding away the limestone underneath the mountain. The cave today is more than 200 meters wide, 150 meters high, and nine kilometres long – it’s home to a river, jungle, limestone “sculptures” and wonderful stalactites.
Mutnovsky Volcano Ice Caves, Russia
On Russia’s Kamchatka Peninsula, ice and fire meet in spectacular form to create an otherworldly cave that glows with the light of the sun. The cave was formed by an underground hot water spring that flows through glacial fields at the bottom of Mutnovsky Volcano, while the walls are made up of highly compacted snow, which is what gives it its unique appearance.
Cave of the Crystals, Mexico
Set below the working Naica Mine in Mexico, the Cave of the Crystals is home to some of the largest natural crystals ever found. Around 300m below the Earth’s surface, the cave houses giant selenite crystals, formed by hydrothermal fluids emanating from the magma chambers below. The cave is currently closed to the public due to its depth, but there are plans to open it in the future.
Vatnajokull Glacier Cave, Iceland
This cave is located in Iceland’s Vatnajokull Glacier, the largest glacier in Europe. A monster truck will transport you to the entrance of the ice tunnel, and along the way you’ll visit lava fields, hot springs and waterfalls. Inside the cave, crafted from melting ice water, you have the opportunity to glimpse more than 2,500 years of ice sculpted by the hand of nature.
Batu Caves, Malaysia
Thought to be more than 400 million years old, the Batu Caves are a labyrinth of limestone caves in Malaysia’s Selangor district. While the caves have held many purposes over the years, today they are home to one of the most important collections of Hindu shrines outside of India, dedicated to Lord Murugan.
Waitomo Glowworm Caves, New Zealand
At Waitomo on the North Island of New Zealand, these caves are known for their population of Arachnocampa luminosa, a glowworm species found exclusively in New Zealand. Here, the insect hangs glistening silken strands from the ceiling of the cave and glows to attract unsuspecting prey. Organised tours include a boat ride through the caves, underneath the glowworms.