As a waterfall retreats, it leaves behind the steep-sided valley which is called a gorge. Every time the overhanging rock breaks off the gorge retreats and grows longer.

Find out more about the landforms of erosion in the upper course of a river.

Formation of a waterfall

Find out more about the landforms of erosion in the upper course of a river.

Rapids form when there is vertical bedding which is when alternate bands of hard and soft rock cross the channel. Differential erosion will occur as the soft rock is more easily eroded than hard rock. This makes the riverbed uneven and river’s flow becomes turbulent leading to white water sections typical of rapids.

Find out more about the landforms of erosion in the upper course of a river.

The characteristics of rapids include:

• the turbulent flow of water
• white water
• uneven river bed
• steep gradients.

Find out more about the landforms of erosion in the upper course of a river.

Interlocking spurs are fingers of land that jut out into the river valley that streams and rivers are forced to flow around in the upper course.

Find out more about the landforms of erosion in the upper course of a river.