As the sun sets on the horizon, I set up my tent on the sand.
My fellow campers are busy preparing their beds for the night. I leave the door open and lie back on my sleeping bag and take in the magnificence of our surroundings.
This spot in Vietnam is a stretch of sand like no other, as it lies deep within the Phong Nha-Ke Bang National Park, inside the colossal chamber of Son Doong Cave.
Exploring the interior is like exploring the heart of the Earth.
Only 1,000 visitors are allowed annually, in groups of 10, so the six-day trek sells out quickly with the only approved tour operator, Oxalis Adventures.
Laura Sharman remembers pitching her tent on the sandy shore of Son Doong Cave in Vietnam. The first night of her six-day trek was spent camping on the beach at Hang En Cave (file image above)
Vietnamese officials have confirmed the cave is the largest in the world. Guinness World Recordswhich in 2012 declared that it is 200 meters high, 150 meters wide and “at least” 6.5 kilometers long.
At the time of acknowledging the record, the organization admitted that the cave could be even larger, because it had not been fully inspected.
The Adventures of Oxalix It is close to 9 km (5.5 mi) long, with enough room for its extensive jungle, river and weather system, and a 60-story skyscraper.
Remarkably, it remained sealed for millions of years before being discovered by accident in 1990.
It was a local man named Ho Khanh who stumbled upon the underground wonder while seeking shelter from a storm, my guide tells me.
The villager had been searching for an expensive plant known as agarwood and came across the entrance to a cave beneath a cliff, but as he approached he saw mist rising from it with the sound of a roaring river inside.
Almost two decades later, its location was shared with caving experts and the first pilot visits were made in 2013, followed by The official launch of the Son Doong Expedition one year later.
It is the most surreal campsite I have ever been to.
As I look out of my tent, I take a deep breath as the sun casts an enchanting glow throughout the cave chamber.
The distant echoes of trickling water provide a soothing lullaby as I snuggle up for the night, enveloped by the massive limestone walls that surround me.
Vietnamese officials and the Guinness Book of Records have confirmed the cave is the largest in the world, stating in 2012 that it is 200 metres high, 150 metres wide and “at least” 6.5 kilometres long.
Son Doong is located deep in the Phong Nha-Ke Bang National Park in Vietnam
In the misty morning, the first rays of sunlight penetrate through the cave opening, reminding us of the dense forest above.
By now I know it well after the two-day hike to get here by climbing rocks, ropes and using ladders.
It all started with a minibus that dropped us off at 9am at the top of a valley and then a descent into the jungle.
Water seeps through my boots as we wade through shallow rivers and streams, but they provide the grip I need for the steep climb up to the first camp at Hang En Cave, the first of two caves on this expedition.
As I approached its mouth, I might have fooled myself into thinking that we had arrived at Son Doong earlier than expected.
It is the third largest cave in the world, with a ceiling reaching 145 m (475 ft) at its highest point, and the widest section of the passage reaching up to 200 m (656 ft), according to The Adventures of Oxaxlis.
Arriving at Hang En Cave above, Laura says she might have been fooled into thinking her group had reached Son Doong earlier than expected due to its large size.
Its magnitude is impressive, with a ghostly atmosphere. The only sound to be heard is the song of the swifts, which can be heard but not seen.
“This cave gets its name from the birds that nest here,” our guide told us.
There will be time for a quick swim in the river while our porters prepare the galley and the chefs prepare various dishes for dinner.
We then recharge our batteries for the next day, which includes walking through the cave, crossing rivers and climbing steep slopes.
I realise how Son Doong remained hidden for so long when we reach the opening and descend 80 m (262 ft) underground, using ropes.
The huge cave passage slowly appears as we descend and the temperature immediately drops.
After much bouldering and climbing, we reached the next camp, this time inside the epic Son Doong cavern.
It’s the moment we’ve all been waiting for and it feels like we’re entering another world.
The rock cavern is so high that it leaves you speechless, especially when you crane your neck to look up at it.
Light streams through the chamber door, highlighting the bright green foliage beyond.
But it is not enough to warm the sand on the ground, which is cold between my fingers.
Son Doong Cave remained sealed for millions of years before being discovered by accident in 1990.
In this desolate environment, we are surprised to find toilets and changing tents, making our night the most comfortable yet and I look forward to getting a good night’s sleep in this dark cocoon.
Emerging the next day, we climbed the steep walls of the cave and made our way through small gaps to reach the forest inside.
The still, cold air has a purity like no other and faint flashes of light are seen in the darkness, which we share with bats, spiders, fish and scorpions.
But all I see of these cave dwellers is the shadow of bats as they descend from the ceiling at dusk or when they are disturbed by the light from our headlamps.
The moment our guide informs us that there will be no more river crossings is a delight; I stop to change into a dry pair of socks.
As I leave the cave, I watch the sun set over the horizon once again and this time it is in full view of everyone.
After several days underground, it’s a beautiful moment, but I would trade it for another night of darkness if it meant returning to Son Doong.
Laura visited Hang Son Doong with Oxalis Adventure. Visit oxalisadventure.com.
