What happens when you skip a rock on a frozen lake? The 'coolest sound ever'

YouTube filmmaker Cory Williams was walking around Alaska when he found a frozen lake and decided to pick up a rock and skip it across the ice.

The result blew Williams’ mind.

“This is the coolest sound I’ve ever heard!” he screams in the video.

The pinging sound is created by the vibration of the ice caused by the rock.