Expedition to the largest cave in the world
Son Doong, Vietnam
The Son Doong cave in Vietnam was only discovered in 2009 and is considered to be the largest cave in the world. Very few people are able to see this unique and strictly protected natural wonder. Our lead explorer Malte Clavin went on a five-day expedition to the underworld.
The British cave explorer Howard Limbert warns us “Never run around the cave without light, as holes or chasms up to 100 meters deep can be found everywhere!”.
I’m sitting in on the security briefing on the grounds of Oxalis the licensee and thus the only organizer of expeditions to the Son Doong cave. Besides me, there are nine other expedition participants, including an American landscape photographer, an Australian oil worker and a Thai YouTube star.
Howard warns us: “Keep your feet dry. Rub them with talcum powder every evening, otherwise this could happen to you”. He shows us horror film worthy pictures of unappetizingly sick looking feet. After two hours of hearing about all kinds of dangers like snakes, abrasions, foot rot and falls, we all shuffle somewhat intimidated into our accommodation.
The next morning there is a lot going on at Oxalis. The entire expedition team is bustling around: 20 porters, 10 members, 5 photo assistants, 2 British speleologists, a Vietnamese cave guide, 2 cooks, 2 national park rangers and the head of the porter group.
The latter monitors the distribution of all expedition luggage: tents, food for five days, clothing, climbing equipment, cookware and cutlery, medication and much more. The porters stuff everything into countless green plastic backpacks until they can hardly be lifted. I notice the shoulder straps of the backpacks, which are only two fingers wide, and I am glad that I won’t be one of the porters for the next five days.
After a one-hour bus ride, the entire team is dropped off at the starting point. We put on our backpacks and march along a steadily downhill path. After about an hour, we cross the Rao Thuong River for the first time.
Our British cave guide Ian ‘Watto’ Watson, a 62-year-old man, powerfully and loudly reminds us in broad Yorkshire slang: “Don’t even think about wringing out your socks, it takes far too much time! We’ll have to cross the river again in two minutes anyway.”
Most of us wear special canyoning boots which expel excess water. I chose cross-country shoes and now I see the tiny print “Gore Tex” next to the laces…e.g. the river water stays in my shoes and a rhythmic squelching noise accompanies me all day long. Suddenly the terrible pictures of the disfigured feet from the night before shoot back into my head, I hope everything goes well!
For two hours we hike further up the river, crossing it countless times in the now relentless, piercing sun. Everything below the navel is and remains, dripping wet. Suddenly the river disappears into an immense rock wall. Watto turns to us: “Welcome to the Hang En Cave! Tomorrow we’ll march through there to get to Son Doong.”
We take a short break and put on our cave gear: a helmet with a powerful lamp and robust gloves that protect us from the razor-sharp rocks. We slowly fight our way up through huge stone blocks in the cave. This is how ants must feel. I look down from an elevated position on our night camp, the tents below appear like colorful Lego bricks in the mouth of a gigantic stone monster.
Half an hour later we reach the camp. A few of us refresh ourselves in the water and let dozens of Gala fish nibble off the remains of our skin. 80 meters above us, thousands of swifts are chirping cheerfully. For dinner, the Vietnamese cook crew conjures up a variety of fresh delicacies from sticky rice, cabbage, omelets, eggplants, tomatoes, onions, peanuts, potatoes and pork from their mobile food stall. “You’ll definitely not lose weight here!” Watto laughs.
Early the next morning we set off to cross the Hang En cave. After about an hour we reach the monumental cave exit.
The huge exit of Hang En Cave. A little above and to the left of the man on the rock in the foreground you can see the tiny cave explorer Ian ’Watto’ Watson in the dry river bed. After three more hours of hiking on and in the river and a few climbs through the densely overgrown jungle we reach the last station before Son Doong cave. I fortify myself with cereal and chocolate bars and put on the climbing equipment.
After a last exhausting passage, we stand astonished in front of a steaming gorge of rock and stone: the entrance to the Son Doong cave! Cold air, deep from the guts of the cave, meets the daytime heat here and condenses into mist. This is exactly where the Vietnamese Ho Khanh stood in 1990 when he sought protection from tropical rain. He climbed a few meters into the cave until it got too steep and slippery.
Ho Khanh is considered the discoverer of the cave, but at that time he had no idea of its enormous size. After an unsuccessful attempt, he was unable to find the entrance until 2008. He then entrusted himself to Howard Limbert, who put together an expedition to explore the cave for the first time a year later. Howard remembers: “Back then when we went in, we didn’t know we were dealing with the largest cave in the world. It was like being a mountain climber and finding a new Mount Everest. It was an absolute treat for us speleologists! ” Directly behind the cave entrance it goes steeply downhill. We rope down 80 meters into the darkness, then cross breast-deep underground rivers and climb over sharp rocks.
Looking back to the entrance of the Son Doong cave, 400 meters away, through which daylight illuminates clouds of cloud where we rappelled 80 meters deep into the cave.
The Son Doong Cave continues to astonish with it’s incomprehensible dimensions
I march again and again through suddenly appearing ‘steam baths’ that obscure my view: underground clouds! Anette, our young Vietnamese cave guide, explains: “The Son Doong cave has its own climate because it is so big. There are several openings in the cave roof so that the air can circulate and create winds”
My headlamp illuminates the path in front of my feet well, but when I look towards the cave ceiling, the light disappears into nothing. The record-breaking dimensions of the cave can only be admired with the help of powerful Swedish cave lamps. With its maximum dimensions of 200 m high,145 m wide and 5 km long, the Son Doong cave is known to be the largest cave passage in the world. This volume corresponds to139 times the Empire State Building. The Son Doong Cave continues to astonish with it’s incomprehensible dimensions. Our assistant, who lights up the ceiling on a rock, is just barely recognizable as a black line. It is also unbelievable that this breathtakingly large and beautiful cave was only fully researched and measured in 2010.
There are no paths, stairs or similar amenities in the Son Doong cave. Every step, every grip must be placed with the utmost attention. Anyone who trips, slips, or slips can easily fall deeply or sprain something. Wounds heal badly in constant humidity. I admire the Vietnamese porters, who jump past me with their tall, heavy backpacks and only plastic sandals on their feet, singing, joking and smoking cigarettes. The Son Doong cave tour is not for the unsportsmanlike or fearful. Again and again we have to rope up, abseil or cross rivers where we sink to our chests.
A sinkhole appears on the horizon, a natural well of light. The underground river has eaten a tunnel through the rock for millions of years
Suddenly a glimmer of light appears on the horizon: a sinkhole, a natural well of light. For millions of years the underground river has eaten a tunnel through the rock ceiling which became increasingly thin and at some point collapsed inwards.
We set up our second night camp in front of the sinkhole. I am grateful to be able to enjoy daylight in the cave.
The next morning we struggle for an hour through huge fallen boulders, always against the light of the sinkhole. A huge green area stretches before our eyes, bordered by a steep, slippery wall that extends vertically 200 meters up to the opening of the sinkhole. I trudge past plants, bushes and trees up to 30 meters high. “This cave jungle is unique in the world” explains Watto, “a delicious cocktail of humidity, bat droppings and daylight has sprouted its own ecosystem here. And because it looks so primeval, my Yorkshire cave buddies named this sinkhole ‘Watch out for Dinosaurs’”
Something very special in the Son Doong cave are the two jungles on the floors of the huge shafts, the so-called sinkholes.
Having reached the opposite end, we descend into the darkness of the cave. Hours later we arrive within view of the second sinkhole. Three assistants go with the strong cave lamps ahead to adequately illuminate our subject, the entrance to the second sinkhole. It takes 15 minutes until they are in position, which we use as a welcome breather. For me, such times are important to keep reminding myself of how special such a place is. I want to appreciate every moment here,-after all, there were already more people on the summit of Mount Everest than in the depths of this cave.
Three people in our group climb the second sinkhole with their headlights on. From my viewpoint, trees are recognizable at the bottom of the sinkhole.
There were more people on the summit of Mount Everest than in the depths of this cave
I set up my tripod and want to clean my camera, but I can no longer find a dry fiber on my body. Hips to shoes are drenched in river water, everything above the hip to below the helmet is sweaty. Tim, the American photographer, stumbles over a stone on his way back and falls unhappily onto his camera. “Shit!” He swears, scowling at his demolished Nikon and the smashed wide-angle lens. Fortunately, he has a second camera with him.
We cross the chamber and reach a lake on the other side. “Hah, what luck!” exclaims Watto, “Normally we’d have to torture ourselves through knee-deep mud, but the rain of the past few weeks hasn’t drained away yet, I can now invite you on a little boat tour!” The first of us board the boats and brightly light up the cave lamps. From where I am I can see 600 meters to the end of the Son Doong cave. It is truly breathtaking. Unforgettable! About 30 meters above the boats you can see a white veil: clouds! The cave has its own climate.
I also get on a boat and paddle to the far end of the lake. Here, at the end of the cave, rising out of the water is the very slippery ‘Great Wall of Vietnam’. In order to get to the back exit of the cave, we would have to overcome the high wall and then torture ourselves through tough morass. Since that would definitely be too dangerous and exhausting, my ‘cavemates’ and I humbly refrain from doing so. Instead, a few of us take the opportunity to strip off our equipment and jump into the wonderfully cool, crystal-clear water. I free myself from sweat, dust and sand, before we return on the one and a half day march back to the entrance of the cave.