A plunge pool is found at the bottom of a waterfall. It is a deep pool into which water from the waterfall plunges. A large pothole is formed by the water swirling and throwing boulders and stones around in circles. There is a lot of spray in a plunge pool at the bottom of a very large waterfall.

Plunge pool on the River Conwy

Plunge pool at the Iguassa Falls on the Parana River

Plunge pool at the Victoria Falls