Quicksand is simply ordinary sand that is so saturated with water that the friction between sand particles is reduced, making them unable to support any weight. ... When quicksand causes the collapse of bridges and buildings, it truly can be dangerous, experts say.

Can you really drown in quicksand?

Nope. Quicksand—that is, sand that behaves as a liquid because it is saturated with water—can be a mucky nuisance, but it's basically impossible to die in the way that is depicted in movies. That's because quicksand is denser than the human body.

What is at the bottom of quicksand?

Quicksand usually consists of sand or clay and salt that's become waterlogged, often in river deltas. The ground looks solid, but when you step on it the sand begins to liquefy. But then the water and sand separate, leaving a layer of densely packed wet sand which can trap it.