What happens when a river suddenly disappears into the ground?

In some places, water doesn't simply flow across the landscape. It can vanish underground through cracks, sinkholes, caves, and porous rock, creating natural drainage systems capable of swallowing astonishing amounts of water.

The Ground Can Swallow an Entire River explores the strange geological processes that allow rivers and streams to disappear beneath the Earth's surface.

Karst landscapes are especially capable of this.

When rainwater interacts with certain rocks, particularly limestone, it can slowly dissolve them and create underground channels, caves, and passageways.

Over time, an entire drainage network can develop beneath the surface.

Some rivers disappear through features called swallow holes or  ...