Getu, China (CNN) — With bare hands, no safety ropes and loosely laced canvas sneakers on his feet, Huang Xiaobao clambers up the sheer rock face with surprising ease.
Below him churn the silted waters of China's Getu River, swollen with the previous day's heavy rain.
Above him in the gloom of the cave is a scarlet Chinese flag, which he unfurls and waves to a small crowd standing on a floating walkway almost 300-feet (100 meters) beneath.
Huang Xiaobao climbs 100 meters without safety protection.
It's a show for tourists, whose gasps suggest they are suitably awed, but Huang's climbing skills were honed long ago for a completely different purpose.
He knows the giant cavern intimately.
As a 12-year-old living in this remote and beautiful part of China he began climbing in search of swallow droppings to fertilize the terraced fields.
Playground for the fearless
Huang climbs for money -- he gets a tiny share of the park's $28 (190 yuan) entrance ticket plus a basic salary of $135 (900 yuan) per month.
But Getu's karst limestone spires, caves and arches are fast becoming a playground for the fearless -- attracting thrillseekers from around the world.
Esteban Degregori and two friends have traveled from Argentina to tackle Getu's Great Arch -- a natural tunnel 165-feet-high (50 meters), 230-feet-wide (70 meters) and 450-feet (137 meters) long.
"The climbing is explosive," he says.
The place was put on the map by Olivier Balma, a French alpinist, who visited in 2007 and was astonished by its potential.
"I was blown away. I knew it could be a world-class climbing spot," said Balma.
Hike through a sinkhole
The less intrepid can still appreciate what Getu, a national park in Guizhou, southwest China, has to offer.
The scale of the karst landscape left me with an otherworldly sense of awe -- a topological oddity that was hard to get my head around.
A path from the park entrance takes you to Swallow Cave -- where Huang performs -- and a floating walkway takes you inside close to where the river plunges into an underground cave network hidden from view.
Not far beyond us lies the world's largest cave chamber, said to be big enough for a 747 jumbo jet. Accessible only via an underground stream, it's not possible to visit it yet.
From there, it's a nerve-wracking climb up to a new glass elevator, which ascends through a second, vertical entrance to the cavity 370 meters above -- what Chinese describe as a "tiankeng" -- a heavenly pit or sinkhole.
Above ground, a grove packed with rare square bamboo and wild banana plants reveals a blind valley encircled by cliffs -- a hidden world blanketed by primeval vegetation.
And just when you think it can't get anymore mind boggling, Getu's Great Arch emerges -- framing a stunning rural vista.
At certain times of the year -- I was told July and August -- sunlight threads through the arch making for a magical if rarely snapped photograph.
The hike takes about two to three hours -- a boat takes you back to the park entrance or up stream to a small village in the park, where I stayed overnight.
Getu River, sometimes called Gebihe, was only connected to China's road network in 2003 and it's still not an easy place to get to.
Local authorities have high hopes for tourism in the region, which is a national park.
A huge car park has been built at the entrance in anticipation of scores of tour buses and the rough road from the nearest town Ziyun, which is connected by highway to the provincial capital Guiyang, is being upgraded.
For now, the number of visitors is more a trickle than a flood -- I visited during a national holiday in June and didn't see any crowds.
Most climbers who visit stay in the village just outside the entrance -- cheap accommodation and food allow them to explore the many peaks and crags for weeks.
Even though the routes are bolted for sport climbing, it's not really a place for beginners, says Mike Dobie, a U.S. climber who's been at the forefront of climbing development in China.
Those who want to learn to climb in China would be better served by Yangshuo, he says -- a more developed and equally stunning rock climbing destination some 370 miles (600 kilometers) away.
For adventurers who prefer riskier, bolt-free climbs using the natural cracks in the rock, the sandstone canyons in Liming in Yunnan province are an emerging place for traditional, or trad, climbing.
Ironically, the influx of foreign climbers to Getu comes just as locals are seeing their skills die out.
Huang is one of just six "spidermen" (their ranks actually include one woman) from the local area who perform their jaw-dropping stunts for tourists up to three times a day.
They're finding it hard to recruit fresh blood. He says his three children can't and don't want to climb.
He wants to teach some of the younger villagers to climb but hasn't been able to find anyone to follow in his footsteps just yet.
Like many areas of rural China, it's common for young people to leave the village to find work in richer cities. Some return, others do not.
Huang says he's never fallen -- but the near daily show climbs take their toll. His muscled hands that seem too big for his slight frame are gnarled and calloused.
He uses the same route each time but takes it slower when it rains.
At 56, he has no plans to retire.
"It's better than farming," he says. "Dangerous, but not as tiring."