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.

A gorge is a narrow, steep-sided valley, with bare, rocky walls.

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

A waterfall is a step in the long profile of the valley. It is where water falls down the vertical drop in the channel usually from a considerable height.

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

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.

Waterfalls and gorges are typically found in the upper course of the river.

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