The World's Largest Natural Arch Is A Secret Stone Landmark Towering Over A River In China

In southern China's lush Guangxi Province, a hidden gem towers over the serene Buliu River. Its scale is awe-inspiring, and its presence is a marvel of nature — yet, for years, it remained virtually unknown outside the local region. In 2009, Jay Wilbur, a founder of the Natural Arch and Bridge Society (NABS), spotted what seemed to be an immense structure on Google Earth. With little documentation to rely on, he and fellow adventurers set out to investigate. Their 2010 expedition confirmed what satellite images hinted at: this was no ordinary rock formation. The Xianren Bridge, also known as the Fairy Bridge, spans roughly 400 feet, making it the largest natural arch on Earth.

The Xianren Bridge is a natural masterpiece. The limestone arch gracefully bows over the Buliu River, creating a 230-foot high opening. This geological marvel is tucked away in rugged terrain, accessible by a raft journey down the river. China offers plenty of other convenient attractions, from bustling cities to the world's largest indoor amusement park with a rainforest. Those willing to venture off the beaten path will be rewarded with breathtaking scenery, such as the Hallelujah Mountains in a national park that inspired Avatar and, of course, the Xianren Bridge, which proves that Mother Earth really is a sculptor.

Reaching the Xianren Bridge is as much an adventure as seeing the wonder itself. One way to start your journey is at the Buliu River Scenic Spot, accessible via a winding mountain road. From there, you can hop on a bamboo raft to be taken upstream. Alternatively, opt for the more thrilling three-hour rubber raft ride downstream from Buliu village. On the raft trip, you'll be greeted with some rapids and stunning scenery. Towering limestone cliffs and weeping willows line the riverbanks, while herons soar overhead and monkeys peek out from the dense greenery.

As the raft rounds a bend in the river, the Xianren Bridge reveals itself in all its glory, soaring over the Buliu River. This geological marvel is a meander natural bridge, meaning its formation is tied to the flow of water. The process begins when a river carves through rock, creating a slender wall between two streams or a single stream's bend. Over time, erosion weakens the rock until it collapses, leaving behind a majestic arch. The Xianren Bridge continues to evolve as water flows beneath it. As you pass beneath the limestone arch's impressive 400 feet, you'll sense nature's grandeur.

The Xianren Bridge is located within the Leye-Fengshan Geopark, a UNESCO site renowned for its dramatic karst landscapes. This area is a treasure trove of geological wonders shaped by flowing rivers that have carved otherworldly formations into the limestone. Among the karst highlights are tiankengs (enormous sinkholes), underground rivers, and cone-shaped peaks known as fengcong. These formations, or geosites, tell a story millions of years in the making.

In 2022, the geopark made headlines when scientists found a sinkhole with a hidden forest. From the bottom, historic giant trees tower over 100 feet. The finding is a testament to the unique geology of southern China. George Veni, director of the National Cave and Karst Research Institute, told Live Science, "Because of local differences in geology, climate, and other factors, the way karst appears at the surface can be dramatically different." This is what's created the splendor of sites like the Xianren Bridge and the karst peaks around Fenghuang, one of the best lesser-known destinations in Asia.

Don't miss the Sanmenhai National Park, another highlight of the geopark. Accessible via public bus from Fengshan, this site offers boat tours along a subterranean river. The journey passes through three skylights — openings carved by sinkholes where the sun pours into the caves. It's an otherworldly experience and a perfect complement to the Xianren Bridge. While information on the geopark is scarce online, travelers should pack their sense of adventure and let the magic of discovery do the rest.