The surface of the Earth is made of rock. You can easily see some rocks above the ground, as in the pictures. Others are deep under the ground or under water.

This rock is made of sandstone.

These rocks are made of granite.

This sea arch is made from rocks.

These limestone rocks are in Bulgaria.

There are many different types of rock. They have different colours. They can be hard or soft. They can be small or large.

A quarry is a place where rocks are dug from the ground. The rocks are taken from the quarry for us to use. Workers use machines to dig and move the rocks.