Vietnam Is Home To The Largest Cave In The World With Its Own Weather System

There are plenty of "must-visit" bucket list destinations around the world that don't live up to the hype. Places you see on travel blogs that look out-of-this-world gorgeous in photos, but are disappointing in real life. In far too many Instagrammable destinations around the world, the colors just aren't as vivid, or there are just too many other people crowding in to try and get the famous shot that deserves a place on the grid. On the other hand, there are also spots that no photo can do justice to, places that have to be seen to be believed. Many of the most mesmerizing places on Earth are even more astonishing when you visit in person.

One such place is Hang Son Doong, Vietnam's natural cathedral of stone, the largest cave in the world. Discovered in 1990 by Ho Kanh, a Vietnamese forester looking for shelter from a storm, it remained unexplored until he was able to return with a team from the British Cave Research Association in 2009. It's a staggering, mind-bending kind of place, almost impossible to visually take in or comprehend. 1650 feet high and 574 feet wide, it burrows deep beneath the karst mountains of central Vietnam, stretching for nearly six miles.

Hang Son Doong is located near the Vietnam/Laos border, in Phong Nha Ke-Bang National Park. The nearest city is the coastal town of Dong Hoi, in Quang Binh province. Getting to the cave is quite a challenge. Visitors arrive at Dong Hoi Airport from either Ho Chi Minh City or Hanoi. From there, it's a bus to Ban Doong village, the only settlement located inside Phong Nha Ke-Bang National Park, before setting off on a guided trek that will last four days in total.

Despite its fame, Hang Son Doong is remote enough that visitors to it are extremely limited. In fact, more people have successfully ascended to the summit of Mount Everest than have entered the cave! It was formed between 400-500 million years ago, during the Cambrian-Permian geological eras, and remains largely as it was in prehistoric times.

Hang Son Doong is impossibly huge. The numbers are there, but the printed word hardly does this awe-inspiring place justice. Its main cavern is large enough to fit an entire New York City block inside, complete with skyscrapers. The main opening is large enough to fly a Boeing 747 airplane through. It's so vast that it creates its own ecosystem and weather systems, meaning that you might encounter fog, clouds, or rain on your journey. It boasts the tallest stalagmite ever discovered, at 262 feet, as well as verdant jungle foliage, rainforests, and microorganisms that have entered through various openings along the cave's length. There's even an underground river, the end point of which has never been discovered.

Exploring the cave takes awhile, as you might imagine. Not only does it take a day to get there, but you will also need at least two days inside to properly explore the remarkable natural rock formations, the shimmering waters, baffling forests, and stunning sinkholes that bring in light from the outside. Alongside the standard blind insects and fish that live in most caves, Hang Son Doong offers the chance to discover wildlife like birds, bats, snakes, flying foxes, and even monkeys. Camping in the cave is one of the most surreal and extraordinary experiences possible, and a highlight of the trip.

As well as being exceedingly remote, access to Hang Son Doong is very carefully managed. The cave can only be visited as part of a guided tour, run by Oxalis, the group of cavers who first explored the cave with Ho Kanh. Only 1,000 people are permitted to enter the cave each year, and the tour will set you back $3,000 for the four-day expedition. This is designed to ensure that the unique ecosystem of Hang Son Doong is preserved, with around $600 from each tourist allocated to the preservation of the surrounding national park.

You will also need to plan ahead if you want to visit, as bookings become available for tours during caving season between January and August two years in advance and sell out quickly. If you do manage to book a tour, however, everything is taken care of. You will be met in Dong Hoi, transferred to the national park, and provided with everything you need throughout the expedition, including all equipment, camping accommodation, guides, and food and drink.

If you can't face the expense or time commitment of the full Hang Son Doong adventure, you can get a taste of the excitement by visiting other cave systems within the Phong Nha Ke-Bang National Park. Hang En isn't quite as large as Hang Son Doong, but is still one of the largest caves in the world, and accessible via overnight trek. Hang Tien in the Tu Lan system offers remarkable zip-line experiences, and can be visited on a day trip.