A man stumbled on Vietnam’s Son Doong, the world’s largest cave passage. It took him years to find it again.

Vietnam’s Son Doong is large enough to match a skyscraper, however regardless of its immense dimension, it took 18 years for Ho Khanh, the man who first discovered the entrance, to rediscover Hang Son Doong, deep inside a Vietnamese jungle.

In 2009, Peter MacNab, together with a five-man crew, had been the first to discover the cave after Ho Khanh’s discovery. They descended into darkness, with no thought what lay inside the depths of Son Doong.

“Every corner you went round was completely new, completely exciting,” MacNab mentioned. “And it just kept getting better and better as you went into the cave. It was absolutely spectacular.”

Trekking by means of the jungle to Son Doong

MacNab just lately returned to the cave with 60 Minutes corresponding to Scott Pelley. The solely manner to get to Son Doong is on foot. There was a gaggle of 53, principally porters carrying tenting gear and TV gear, and consultants in security and climbing. Visitors want to splash by means of 20 river crossings on route to the cave.

The jungle, in the Truong Son vary between Laos and the South China Sea, is residence to tigers and leeches.

The entrance to Son Doong is tough to find. Ho Khanh was accumulating wooden when he first discovered it in 1990 whereas sheltering from a storm. He remembers feeling one thing unusual: wind blowing out of the floor.

Cavers acknowledged that as an indication of an enormous cavern, so in 2000, British cavers requested Ho Khanh to find the cave once more. In 2008, eight years later, I positioned the entrance once more. Exploration of the cave started in 2009. Today, there’s writing on the wall exterior, proclaiming the miracle of Ho Khanh.

World’s largest cave passage began with a crack the width of a strand of hair

Visitors descend down a 30-story wall into darkness as they enter the cave. At the backside is the Rao Thuong River. Its water is acidic, so it’s good at dissolving limestone, enabling the creation of the cave.

The formation of the cave began round 2.5 million years in the past, Purdue University geologist Darryl Granger, who first got here to Son Doong in 2010, mentioned. It’s believed the river discovered a tiny crack,”the width of a hair,” in the limestone ridge.

“That’s all it takes to make a cave. The water started flowing through it and dissolving it bigger, and bigger, and bigger,” Granger mentioned. “We still have water going through it, today. So, it’s continuing to get bigger, as we speak.”

Water flows by means of the cave all through the yr. In the dry season, individuals can move by means of. During the 4 months of moist season in fall and winter, visiting is unattainable.

“In flood, the water’s over our heads,” Granger mentioned. “We get 300 feet of water in this cave. And it’s not just, like, a bathtub; this is a raging river. And that water is able to dissolve the limestone and carry it out of the cave.”

Three days in Son Doong

Granger additionally joined 60 Minutes, together with cave explorer Howard Limbert, who over a interval of many years, found round 500 caves in Vietnam. Limbert described the trek by means of Son Doong as “the best adventure that happens in the world.”

“That’s the beauty of caves,” Limbert mentioned. “If you’re climbing a mountain, you can see where you’re going, but in a cave, when you go in, you don’t know what it’s going to do.”

60 Minutes’ journey by means of Son Doong took three days and two nights. It’s 5.6 miles lengthy and, in locations, 65 tales tall. The Great Pyramid of Giza would match inside simply. A 747 airplane may fly by means of the greatest passage and never scrape a wing, whereas in different areas, the solely manner ahead was by means of tight passages.

There’s no cellphone reception in the cave, leaving guests minimize off from the world.

Roughly midway by means of the cave is the first of two dolines, skylights the place the roof collapsed. They’re a break from the whole darkness. As the cave grew over hundreds of thousands of years, the limestone at the high was unable to help the roof above, making a break in the ceiling. With daylight streaming by means of the doline, the jungle entered the cave.

Continuing on, there’s an underground lake, then a steep, 30-story wall, referred to as “The Great Wall of Vietnam.” MacNab ran out of time on his first go to to the cave, so he did not attain the finish throughout his first expedition.

It’s a 300-foot climb on slick rock with no footholds wherever.

“It’s challenging enough until you realize, of course, you are doing it in the dark and it’s, essentially raining. The ground water is coming from the roof,” Pelley mentioned.

MacNab mentioned he returns to Son Doong each two years.

“And we’ve barely scratched the surface of the caves in this area,” he mentioned.

But there’s a deadline. The marvel of Son Doong is not going to final, though the final finish will not come for just a few million years. Erosion will win in the finish, and the roof will collapse.

The world’s largest cave will, at some point, change into a canyon.