A Photo Journey Inside Hang Son Doong – The World’s Largest Cave

At the beginning of 2015 we were lucky enough to take part in a 5-day expedition to Hang Son Doong, the world’s largest cave. Run exclusively by the adventure tour company Oxalis, we had been spending a few months in the town of Phong Nha, close to where the cave is located. Through a number of cancellations and an opportunity to do some work with Oxalis, we had been given the opportunity to visit this true wonder of the world.

Hang Son Doong was discovered in 1990 by Ho Khanh, a local man who was out hunting in the Phong Nha-Ke Bang National Park. While seeking refuge from an approaching storm he found a large opening in the side of a cliff, with clouds billowing out. He neared the entrance and could hear a river deep inside. The steep and dangerous rocks meant that Ho Khanh was unable to explore further, and he left once the storm passed.

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Around the same time Howard and Deb Limbert, two caving experts with the British Cave Research Association, were living in Phong Nha spelunking in the area. Over dinner one night Ho Khanh mentioned his find to Howard and Deb, but admitted that he had now forgotten where it was. Knowing that the presence of clouds and an underground river meant something substantial was there, Howard and Deb urged Ho Khanh to try and find it again. For the next two decades their search turned up nothing.

Ho Khanh Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
Ho Khanh, the local man who discovered Hang Son Doong. We were lucky enough to have him join us on our expedition.

However things were to suddenly change, and in 2008 while on another hunting mission Ho Khanh found himself in a section of the jungle he recalled to be near the entrance he found all those years ago. He managed to find it, and carefully retraced his steps back to Phong Nha village to report his discovery to Howard and Deb. The monsoon season soon kicked in, and the exploration would have to wait until the following year.

In 2009 Ho Khanh returned, this time with the aid of the BCRA. They began their exploration of the cave, which led them to a giant wall that hindered any further progress. In 2010 they managed to scale the wall, which they called the “Great Wall Of Vietnam”, and find the other exit to the cave. At this point they realised that the cave was the biggest ever discovered. Named Hang Son Doong, meaning “Mountain River Cave” in Vietnamese, it is now open to small expedition groups.

The discovery of the world’s largest cave in one of the poorest provinces in Vietnam has brought about an incredible surge in community-based tourism, which is positively affecting the lives of many locals. Besides the ecological marvels of what lies beneath the jungle, the way people are able to benefit their lives from its existence is one of the real wonders of Hang Son Doong.

More people have stood on the summit of Everest than have stood inside Hang Son Doong, and we were one of the lucky few to get to experience this impeccable adventure. This is our photo journey to the heart of Hang Son Doong.

Sunbeam Doline 1 Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
With the colossal size of the caves in the Phong Nha-Ke Bang National Park and the high levels of rainfall the region receives, erosion happens at an accelerated rate. Occasionally the weight of the limestone gives way and collapses, creating what is known as a ‘doline’. Derived from the Slovenian word ‘dolina’, meaning ‘valley’, these sinkholes create huge gateways to the outside world. At certain times of the year when the conditions are right, incredible sunbeams penetrate through these exposed sections and into Hang Son Doong, creating mesmerising light shows.
Hang En Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
On the first day of the 5-day expedition you reach Hang En, the third largest cave in the world. Meaning “Swift Cave”, Hang En has been used by local tribesman for time unknown. They have been discovered free climbing the dangerous cliffs in search for the swallows that live in the cracks – considered a local delicacy. The minority groups are never seen during the tourist season though, and the inside of Hang En serves as a base on the first and last nights. This campsite is perhaps one of the most spectacular in all of Asia.
Chamber Of Light Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
The cave systems of Phong Nha are immense, and the national park contains the current title holder for the largest ever discovered, Hang Son Doong. Interpreted as ‘Mountain River Cave’, the largest chamber measures 5km long, and peaks out at 200m high and 150m wide. The only way to get a true sense of perspective on the sheer size of Son Doong is to have fellow trekkers scatter throughout the limestone galleries. Even then it is hard to properly comprehend the enormity of a place that could house an entire New York City block, all underground.
Porters Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
In the same way the Sherpas of Nepal are instrumental to a climber’s success in summiting Mount Everest, the local porter’s of Son Doong are the true heroes of this multi-day caving expedition. These men all hail from Quang Binh, one of the poorest provinces in Vietnam, and come from a variety of working backgrounds such as farming, hunting and logging. One thing they all have in common is their astounding ability to survive and thrive in the jungles of Phong Nha. Twenty porters, two chefs, two national park rangers, two assistant guides, one lead guide and two British caving experts make up the team that take a group of ten customers on the 5 day, 4 night journey inside the world’s biggest cave.
Hang En Exit Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
This exit of Hang En is one of the largest ever discovered. From the sand to the ceiling is over 120m tall, and the width is over 140m. Caving experts believe this to be close to the maximum size possible, as the weight of the limestone above could force a collapse at any time. To get a true scale of the immensity of this exit, study the size of the people standing in the centre of the opening.
Porter Sandals Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
Many people who undertake serious outdoor expeditions spend hundreds of dollars on specialty shoes armed with the latest in adventure footwear technology. The jungle men of Phong Nha wear plastic sandals purchased from the local market at the cost of 20’000 Vietnamese Dong – the equivalent of about US$1. They nimbly skip from boulder to boulder, ford fast-flowing rivers and trek for weeks on end through dense forest wearing these basic shoes. Observing foreign tourists struggling to negotiate the difficult terrain in sometimes thousands of dollars worth of gear is fascinating to the porters, who are quite content with their chosen footwear.
Descending Into The Darkness Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
Some sections inside Hang Son Doong require specialist equipment, such as a harness, belay devices and safety lines, in order to safely manoeuvre over cliffs and boulders. Under the supervision of experienced guides we scramble amongst tumbled limestone, sometimes with sheer drops either side of us. While the climbing required is far from being technical, an adequate level of fitness and ability is needed to pass through the majority of the cave. Within minutes we can escape from the outside world and descend into total darkness.
Limestone Formation Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
Limestone formations such as stalagmites and stalactites are formed when water containing dissolved calcium carbonate drips through the cave’s ceiling and creates minuscule rings. Over millions of years these tiny minerals grow in a collection of striking and often beautiful shapes. The development is very slow, varying between 0.007mm and 1mm annually. Research in Vietnam has never been specifically undertaken to see exactly what the localised rate of growth is. The general consensus is that it is much higher than average, due to the average 2500mm of rainfall received every year and the high levels of condensation that build up inside the caves. As a result the formations in Phong Nha are amongst the biggest found anywhere in the world, such as one 80m high stalagmite in Hang Son Doong – the tallest ever discovered.
Cave Pearls Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
It’s not just the enormous formations which are incredible inside Hang Son Doong. Also discovered are rare, spherical limestone pieces known as “cave pearls”. These are formed from a tiny nucleus spinning over thousands of years, collecting calcium salts as layers.
Porters Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
Entertainment comes in many forms when you spend days on end inside a cave. Card games are popular, as is singing songs and drinking potent, locally brewed rice wine. The Vietnamese porters take pride in their strength and agility and are constantly challenging each other to show off their skills. Arm wrestling is one such activity and the men enthusiastically try to get everyone involved. Despite their small stature, their levels of energy and strength are impressive and they constantly out-perform professional athletes who come to explore the caves.
Campsite Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
Camping inside Hang Son Doong is quite possibly the most unique and incredible experience you can have anywhere in the world. Every season the porters carry in enough equipment to create the site, including tables, chairs and even toilet facilities. At the end of the season everything is carried out, including the waste.
Jungle Clouds Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
Hang Son Doong is so massive that it contains its own jungle, underground river and localised weather system. Clouds form inside the cave and spew out from the exits and dolines, which gave the first explorers a clue as to how large Hang Son Doong really is. As you trek through this section of the cave, known as the ‘Garden of Edam’, clouds filter through the trees creating a prehistoric atmosphere. Completely engulfed by karst cliffs and towering foliage, with a vast exposed ceiling above you, it is easy to forget that you are actually deep inside an underground cavern.
Underground River Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
The Rao Thuong River flows fast through the Son Doong cave system, continuously carving new chambers and passages. During the wet season the river floods to dizzying levels, halting any chance of exploration through the caves or jungle. The water shines in bright hues of blue and green as a result of most of the sediment being filtered out by the limestone. Rao Thuong River must be crossed numerous times in order to reach the giant cave system. Once inside, a guide rope is used to assist in fording sections of the river safely.
Watch Out For Dinosaurs Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
The viewpoint looking back at “Watch Out For Dinosaurs” offers a truly magnificent sight. Clouds roll in from the jungle outside, and with the right conditions small waterfalls tumble down, creating a visual experience like no other.
Campfire Cooking Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
When the porters and caving experts are on their exploratory missions in the national park, they live on a staple diet of rice and whatever they can harvest from the jungle. In stark contrast, the official tours to Hang Son Doong have two qualified chefs as part of the experienced team. The communal dinners sitting in the shadows of the world’s biggest cave are all the more impressive when you are eating barbecued pork ribs, fried chicken, sautéed vegetables and seasoned tofu. High energy tours require high energy foods, and there is no shortage in the 45kg packs the porters bring with them.
Stars Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
The location of the second camp inside Hang Son Doong lies at the bottom of a steep rockfall coated in moss and shrubs. From your tent you can stargaze up through Doline 2, while the dark abyss of the rest of the cave menaces directly behind you. The local porters all favour this particular campsite over the others. Most of the local men are very superstitious and maintain a deep fear of caves. They take comfort in being able to stare up at the jungle and open sky. To them, the jungle is home and always will be.
Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
In this shot Lesh stands behind the campsite in Hang En, where a narrow slit allows passage between both exits.
Proposal Engagement Hang Son Doong Photography Tour World's Biggest Cave Vietnam Phong Nha
At the base of Doline 1, having just moved through Watch Out For Dinosaurs, I asked Alesha to step up onto a limestone formation for a photo. With the rare sunbeam glowing brightly behind us, we looked into each other’s eyes. She asked me how we should stand for the photo, and I said that I had an idea. At this moment I dropped to one knee and told her that my love for her was larger than anything in this world, the cave included. With a tear welling up in my eye I asked the girl of my dreams to marry me. She closed her eyes, started crying and said “yes”.
About the Author - Alesha and Jarryd

Hey! We are Alesha and Jarryd, the award-winning writers and professional photographers behind this blog. We have been travelling the world together since 2008, with a passion for adventure travel and sustainable tourism. Through our stories and images we promote exciting off-the-beaten-path destinations and fascinating cultures as we go. As one of the world's leading travel journalists, our content and adventures have been featured by National Geographic, Lonely Planet, CNN, BBC, Forbes, Business Insider, Washington Post, Yahoo!, BuzzFeed, Channel 7, Channel 10, ABC, The Guardian, and plenty other publications. Follow our journey in real time on Facebook, YouTube and Instagram.

24 thoughts on “A Photo Journey Inside Hang Son Doong – The World’s Largest Cave”

  1. Wow, awesome pictures of Hang Son Doong! Nowadays the waiting line is about 3 years so you can really be lucky to having this experience tucked away already! I wish I can go some day as well 🙂

    • Thank you so much Chris. We appreciate it. That is right. There is only allowed so many people in the cave a year to protect it. The company, Oxalis, that has the contract for the tours, protects the cave very well. Everything that goes in, comes out. There is a path in and out that is follow by the adventurers so no vegetation is damaged. We really hope you put your name on the list. It is an experience of a life time and definitely worth waiting for. Safe travels

  2. Hey..great trip guys. I have a question for you. How much did it cost the tour to Hang Son Doong cave with Oxalis? I was there in 2013 but at that time the expedition cost soooooo much!!!

    • Hi Enrici, thank you so much. It was a trip of a lifetime. AMAZING! It definitely cost a bit and is worth every penny. It is a big expedition and their mission is to protect the environment. Last we heard it was about $3000 USD but it may have changed. Send them an email. They are very quick in replying. https://oxalis.com.vn/cave/son-doong-cave/

      All the best

  3. This is a superb post with stunning images. I think we have just found something new to add to our bucket list!

    Julie

    • Thank you so much Steve and Julie. It was a highlight of our Vietnam trip. Definitely get there soon. The area is changing and so it things with the cave. We heard they might be putting in a cable car. Very sad. The town Phong Nha is an amazing place also. People who usually go on a cave tour go in and out and don’t see much of the town. Stick around if you go. It is a beautiful place with so many wonderful guesthouse. Happy planning.

  4. What a great photo-essay. This had been on my bucket list until I saw the price of the expedition. Thanks for taking me there via the post. Maybe I will need to find a way to afford this afterall. Oh, and what an awesome way to propose 🙂

    • Thank you so much. That was a surprise. I had no idea it was coming. Jarryd definitely got me. We understand about the price. It is an expensive tour but so are many other tours in the world. Personally, we think it is worth every penny and it is a once in a life time experience. We loved every minute of it. It is a massive expedition with 10 guests, 23 porters, 2 cooks, 2 guides and 2 caving experts. Everything that goes in, comes out. We hope you do get there one day until then happy travels. 🙂

  5. Great overview and pics! Thanks for sharing.

    • Thank you so much for reading Gaz.

  6. We had seriously contemplated visiting here last year, but the price was more than we could afford at the time and deterred us. You were indeed incredibly fortunate to have visited there! WOW! Maybe one day I’ll get there. Loved the photos! <3

    • Hi Hali, thank you for your comment. It all depends if you really want to do it. If you definitely do, you’ll find a way to save up the money. For us it was a once in a life time experience. We did look at the money and thought, “you only live once, let’s do it”. We were so glad we did. Personally, we think it is worth every penny. It is a massive expedition with 10 guests, 23 porters, 2 cooks, 2 guides and 2 caving experts. Everything that goes in, comes out. A lot of work come behind the tour that the guests don’t see. We got to the meeting point early and watched all the porters pack up everything. It was amazing to watch. Each were carrying about 25 kg on their backs and that is light for them. Hope you get there one day. All the best

  7. What an amazing story! Hang Son Doong is one of the largest caves in the world, definitely. There are a few others just as big! Including the one in Borneo at Mulu caves. We’ve been to that one and it is awesome! However at 3k a person a trip to San Doong isn’t exactly feasible without some help from a magic fairy money godmother lol. We recently did another trek with Oxalis and aren’t they a great company! You guys got very lucky. And what an incredible story to tell everyone about where you got engaged! Not every day people do that in one of the biggest caves in the world 🙂

    • Hi Mica, we are so happy you did a tour to one of the caves with Oxalis. They definitely are a great company. There are a lot of big caves in the world. Hang Son Doong has the largest known cave passage cross-section in the world and i think Mulu caves is the longest but don’t quote me. We would love to get to Borneo one day and explore the Mulu Caves. Bet it is was a great adventure. As for the price…. Personally, we think it is worth every penny and it is a once in a life time experience. We loved every minute of it. It is a massive expedition with 10 guests, 23 porters, 2 cooks, 2 guides and 2 caving experts. Everything that goes in, comes out. A lot of work goes on behind the scenes that guests do not see. A gorilla tour in Africa is $1000 USD per hour….. now that is crazy. But we’d definitely still do it. 🙂 Happy travels

  8. Thanks so much for bringing me there with you! I don’t have the best health right now so travel mainly to eat (a great sitting activity) but hope to do things like this when I’m healthier. Thanks again for sharing!

    • You’re welcome Sarah. Hope your health improves soon and you get a chance to do some caving again 🙂

  9. Whao, unbelievable!

  10. Hey guys! So cool to finally see your trip to Hang Son Doong! Looks like a truly amazing experience- And, nice job with the photos, they turned out awesome!

  11. Absolutely brilliant, that. What an adventure. Superb photography, as well. I love stories like this. I’m chilling out in Spain at the moment, which is lovely, but this post has given me itchy feet! Good job I’m off to South America in the new year! Love your blog, you two.

    • Glad you enjoyed our post Carolyn. Enjoy South America! I’m sure you’ll have a sick time. We’ve never been unfortunately.

  12. I posted before I remembered to add, Congratulations!!!

    • Thanks mate!

  13. Thanks for the great post! I am on the 12 March 2016 5-day expedition and was already waiting with great anticipation. Your post has me drooling…

    • You’re going to love it mate! Definitely one of the best things we have ever done.

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