Sea Caves – Large holes in the cliff caused by waves forcing their way into cracks in the rock

We all know what a cave is, but how are they formed on the coastline?

Waves crashing against the base of a cliff can sometimes form a cave. A large crack can open up by hydraulic action. Sea caves form along a crack in a rock or where the rock is softer.

The crack grows into a cave by hydraulic action and abrasion.

The cave becomes larger. Caves are typically found in sedimentary rock, which is relatively soft. They are less common in harder granite rocks.