Jungles of the Underworld
The ground quivers and collapses into a giant cavern, revealing towering trees and lush forests full of unknown species.

The image here is not of the described sinkhole. Credit: Xinhua.
Southern China is one of the most spectacular places on Earth. The special karst topography allows life to flourish not only on the land's surface but underground as well. Karst regions are found worldwide, but China's karst Guangxi Zhuang Autonomous Region is so extraordinary that it's been designated an UNESCO World Heritage site.
Wait, what is karst? Karst is a kind of cavernous landscape formed by the dissolution of rock from rainwater. As rainwater flows, it carries with it carbon dioxide, which makes it slightly acidic. This acidic water eats through the rock, forming caves and tunnels underground. When the caves get big enough, they collapse under their own weight, forming otherworldly sinkholes and revealing entire hidden ecosystems. Locally, these sinkholes are known as "tiankeng", which mean "heavenly pit". And they certainly are heavenly.
Just take a look at one of the Guangxi region's most recently formed tiankeng. At over 190 meter deep and over 300 m (100 ft) long, it's a paradise for giant trees towering over 40 m (130 ft) tall and plants that can brush a tall man at the shoulder. It's also very likely that tiankeng like this one are home to undiscovered species. The water that flows through these caverns quenches the thirst of the local life and allows it to thrive. They also provide water for the local human inhabitants as well. See the beauty for yourself:

Source: Livescience.com

Credit: Public domain

Credit: Metajuannews.com

Credit: ECNS

Credit: Song Wen/Xinhua/Alamy Live News
Source: Pappas, S. Giant sinkhole with a forest inside found in China. (2022). LiveScience. https://www.livescience.com/new-sinkhole-discovered-china
And here are some more spectacular photos from southern China's karst regions:

Credit: Pinterest

Credit: Pinterest

Credit: iStock

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