Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsA previously unexplored tiankeng near Ping’e village in China’s Guangxi Zhuang Autonomous Region contains a remarkably well-preserved forest. Explorers reached the floor on May 6, 2022, finding trees nearly 40 metres high, shoulder-level shade plants and three large caves in the sinkhole walls. The forest is often described as ancient or primitive, but no published dating establishes that it has been isolated for a specific number of millennia.
Where is the giant sinkhole in China?
The sinkhole is near Ping’e village, in Luoxi township, Leye County, Guangxi Zhuang Autonomous Region. It was explored by a Guangxi 702 cave expedition and is one of at least 30 large sinkholes identified in Leye County, according to Xinhua.
Guangxi is part of China’s extensive karst landscape, where soluble limestone has been shaped by water into caves, underground drainage systems and collapse features.
How big and deep is the tiankeng?
| Measurement | Reported value | Qualification |
|---|---|---|
| Length | 306 metres | Measurement reported by Xinhua |
| Width | 150 metres | Measurement reported by Xinhua |
| Depth | 192 metres | Measurement reported by Xinhua |
| Estimated volume | More than 5 million cubic metres | Reported as exceeding this figure by Xinhua |
Those dimensions make it a large sinkhole, but no definitive worldwide ranking has been published. Claims such as “largest” depend on whether length, width, depth or volume is being compared.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
- Comfortableness: NORTIV 8 Men's Waterproof Hiking Boots certainly delivers on all-day comfort! Removable and shock-absorbent cushioned insoles offer the support for your feet.
- Lightweight and Flexible EVA midsoles: reduce foot fatigue. They are designed for long-lasting comfort, superior cushioning, and high energy return.
- Non-slip & Durable: High-quality rubber soles are fully slip-proof and feature advanced traction for firm stability on challenging terrains. No more slipping and falling on wet or muddy surfaces!
- Outdoor Style: Designed for both daily work and outdoor activities like hiking, hunting, camping, climbing, cycling, fishing, running, backpacking, trekking, mountaineering, traveling, and so on.
- What You Get: NORTIV 8 aims at providing high-quality outdoor shoes.
What explorers found at the bottom
A living forest
On May 6, 2022, expedition members abseiled more than 100 metres into the opening, trekked for several hours and returned safely that evening. At the floor they found a dense, well-preserved primitive forest. Expedition leader Chen Lixin described trees approaching 40 metres in height and shade-loving plants reaching a person’s shoulders. The Guardian reported the same approximate tree height and the unusually intact underground setting.
Three wall caves
Zhang Yuanhai, a senior engineer at the Institute of Karst Geology of the China Geological Survey, reported three large caves in the sinkhole wall. He said they were presumed to be remnants of an early stage in the sinkhole’s development. Their presence, together with the deep opening and forest floor, gives researchers several connected environments to investigate rather than a single isolated cavity.
Rank #2
- OMNI-TECH: For prolonged exposure to moderate rain and snow. Multilayered, waterproof, seam-sealed construction that allows the inside to breathe, keeping feet dry and comfortable no matter the conditions.
- TECHLITE: For lightweight impact absorption on varied surfaces. Long-lasting cushioning with high energy return.
- OMNI-GRIP: For multi-terrain traction on rock, dirt, and gravel, in wet/dry conditions. Specially formulated compounds and tread design for cross-terrain stability and grip with strategically blended lug patterns.
- HANDY FEATURES: This adventure-ready hiker features a durable leather and mesh upper, metal hardware, and a cushioned collar for comfort.
- BUILT TO LAST: Columbia’s attention to detail is what sets our footwear apart. Specifying only the highest quality materials, expert stitching, and craftsmanship. This is long-lasting footwear you will enjoy for seasons to come.
What does “tiankeng” mean?
Tiankeng translates roughly as “heavenly pit.” Xinhua uses the term for giant dolines in karst terrain that develop through repeated cave-ins. National Geographic’s explanation of karst formation describes rainwater absorbing carbon dioxide, becoming mildly acidic and dissolving soluble rock—usually limestone—over very long periods. Enlarged underground cavities can eventually lose support, causing the surface to collapse and create a steep-sided pit.
How could a forest survive at the bottom?
A species-by-species ecological study and measured age for the forest have not been published. They do, however, show conditions that can support substantial vegetation:
Rank #3
- Comfortableness: NORTIV 8 Men's Waterproof Hiking Boots certainly delivers on all-day comfort! Removable and shock-absorbent cushioned insoles offer the support for your feet.
- Lightweight and Flexible EVA midsoles: reduce foot fatigue. They are designed for long-lasting comfort, superior cushioning, and high energy return.
- Non-slip & Durable: High-quality rubber soles are fully slip-proof and feature advanced traction for firm stability on challenging terrains. No more slipping and falling on wet or muddy surfaces!
- Outdoor Style: Designed for both daily work and outdoor activities like hiking, hunting, camping, climbing, cycling, fishing, running, backpacking, trekking, mountaineering, traveling, and so on.
- What You Get: NORTIV 8 aims at providing high-quality outdoor shoes.
- Light: The opening is large enough to admit direct and diffuse sunlight to the floor.
- Water: Karst landscapes channel rainfall through surface openings and underground drainage, supplying moisture even when the surrounding surface is dry.
- Shelter: Steep walls can buffer wind and limit routine human access.
- Isolation: The depth and difficult descent reduce disturbance, allowing mature plants to persist.
- Connected habitat: Wall caves and the floor may provide different humidity, temperature and shelter conditions.
These factors explain why a forest can be both light-accessible and unusually protected. They do not prove that every plant has remained unchanged or isolated for thousands of years.
Were undiscovered species found?
No new species has been confirmed in the published accounts. Chen Lixin said he would not be surprised if future work found species never previously reported or described by science. That is a prediction about research potential, not confirmation of a new species. A formal discovery would require collection or observation, taxonomic analysis and publication by specialists.
Rank #4
- Mens hiking boots made of premium synthetic suede. SL-TEX waterproof membrane prevents water from entering and volatilizes water vapor. Ultra-light weight: 1.25lb (size 10)
- Breathable and skin-friendly D01 lining has efficient ventilation effect and keeps comfortable and dry throughout the day. Features a lace-up for an adjustable, secure fit.
- Closed-cell tongue prevents rain, muck and sand from entering. Rubber anti-collision toe design and the waterproof sealing structure, bring you comprehensive protection and comfort.
- Removable memory foam insole provides excellent arch support to the natural contours of the foot. Targeted heel cushioning improves overall comfort by reducing stress on your foot with each step.
- Flexible EVA midsole bring superior cushioning and high energy return, reduces foot fatigue and absorbs shock. Advanced traction rubber sole provides stable and reliable grip in a variety of environments. Designed for both daily life and outdoor sports like hiking, walking, hunting, camping, climbing, cycling, fishing, jungle, running, backpacking, trekking, mountaineering, traveling, etc..
Why the site matters to science and conservation
UNESCO describes Chinese tiankengs as underground sanctuaries for distinctive plant, animal and microbial communities and notes 40-metre-high trees in a pristine underground forest in the Leye area. This sinkhole offers an unusual natural laboratory because it combines a very deep collapse feature, an opening that admits light, mature vegetation and multiple wall caves.
Researchers can study how karst collapse creates habitat, how plants and microbes move between surface and subterranean environments, and how isolated communities respond to changing moisture and light. The same isolation that protects the forest also makes it vulnerable: climbing, collecting specimens, trampling seedlings, introducing pathogens or altering drainage could damage a system that took a long time to develop.
Best Value
- Excellent Comfort: Nortiv 8 women's waterproof hiking boots use our lightweight, durable midsole, and advanced traction rubber soles, which can be slip-resistant on rugged ground. If you prefer a looser fit, consider choosing the wide toe box version.
- Combinations: This boot uses suede leather and suede ankle boots structure, and its durable mesh tongue provides breathability, allowing you to spend dangerous days on the road comfortably and safely. Single shoe weight: 14.98oz
- Feminine Style: These women's waterproof hiking boots are fashionable, durable, and use a series of contrasting color combinations and a soft suede appearance.
- Advanced Traction: This hiking boot uses excellent technology to provide the ultimate traction and grip in any environment.The slightly firm sole offers durable support and foot protection, while the added EVA insole enhances cushioning for all-day comfort.
- What you get: Nortiv 8 aims at providing high-quality outdoor shoes.
What the reports do—and do not—establish
- The location, dimensions and 2022 expedition are documented by Xinhua.
- The forest’s approximate tree height and preserved setting were also reported by The Guardian.
- Three wall caves were observed, with their evolutionary interpretation presented as a presumption.
- The forest is described as ancient or primitive, but an exact age in years has not been published in these accounts.
- No published account confirms a newly discovered species.
- No reliable “oldest” or “largest in the world” ranking is established without a defined comparison metric.
Can people visit the forest?
The 2022 descent required ropes, specialist expedition skills and hours of trekking. That is very different from ordinary sightseeing. Unless local authorities create a controlled program, visitors should treat the forest as a protected scientific site rather than an informal attraction. Responsible karst tourism should keep people on designated routes, prohibit collecting and avoid introducing food, soil or organisms into the pit.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
