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Glaciers are massive rivers of ice that move across land. They can change the landscape and create glacial features on mountains, like corries and ����ê�ٱ�s.

In this article you can learn:

• What a glacier is
• How corries and ����ê�ٱ�s are formed
• How a pyramidal peak is formed
• How to stay safe when climbing mountains

This resource is suitable for Landscapes topics for primary school learners.

Join Isla and Connor as they climb Ben Nevis and explore features of glaciated erosion: corries, ����ê�ٱ�s and pyramidal peaks.

• A glacier is a huge mass of ice that moves slowly across land.
• A glacier needs very cold temperatures and lots of snow to form.
• Air temperature gets lower the higher up you are from sea level. That's why you can often see snow on mountain tops.
• Glaciers usually form high up on mountains because the temperature is much lower.

During the last Ice Age, Scotland was often covered in glaciers. They formed high on mountains and flowed downhill. Now the glaciers have gone we can see how they shaped the mountains, forming corries, ����ê�ٱ� and pyramidal peaks.

• A corrie is an armchair-shaped hollow found on the side of a mountain. It is the place where a glacier once formed.
• Most corries were formed during the Ice Age.
• Snowflakes collect in a hollow. As more snow falls, the snow gets squashed (compressed) and air is squeezed out.
• Over thousands of years, the compacted snow becomes hard glacier ice.
• The hard glacier ice gets so heavy that it begins to move downhill. Ice that has melted into water underneath helps the glacier to move.
• Eventually, the moving glacier erodes the surface of the corrie. This is glaciated erosion.

Glaciated erosion takes place in two ways:

1. Plucking steepens the back wall of the corrie.
2. Abrasion deepens the hollow of the corrie.

• When two corries form back-to-back, a steep ridge called an ����ê�ٱ� is created.
• When three or more corries erode a mountain back-to-back, the ����ê�ٱ�s form a pyramidal peak. This is the classic mountain shape that looks like a pyramid.

• glacier - A massive river of slow moving ice.
• glacial features - Landscape features that have formed by glaciers.
• corrie - An armchair shaped hollow found on the side of a mountain. This is where a glacier once formed.
• ����ê�ٱ� - A steep ridge created when two corries form back-to-back.
• pyamidal peak - When three or more corries erode a mountain back-to-back, ridges (����ê�ٱ�s) form a pyramidal peak. This is the classic mountain shape that looks like a pyramid.
• compact - When two or more objects are closely packed together and there's no space between them. For example, snow can become compacted so there is no room for air between the snowflakes.
• erosion - Wearing away.
• plucking - When rocks and stones become frozen to the bottom or the sides of a glacier. The rocks and stones are plucked from the ground or rock face as the glacier moves. Plucking leaves behind a jagged landscape.
• abrasion - When rocks and stones become stuck to the bottom and sides of a glacier. The rocks and stones rub against the bedrock (at the bottom of the glacier) and rock faces (at the sides of the glacier) as the glacier moves.
• The Ice Age - A long period of time when the Earth's temperature became very low. The Earth's surface was buried under sheets of ice. It was at its peak about 22,000 years ago.
• munro - A Scottish mountain that is over 3000 feet (914 metres) high.

In the video at the top of the page, Isla and Connor climbed Ben Nevis to explore features of glacial erosion.

Mountain climbing can be very dangerous and you should never try it on your own. Always make sure you have a responsible adult who has climbing experience with you.

You should always tell someone:

1. Where you are going
2. The path you are taking
3. When you expect to be back

Remember to bring:

• Warm waterproof clothes
• High energy snacks and a drink
• A whistle
• A torch
• A first aid kit
• A map
• A compass

Find out more:

Design your own 3D mountain.

Use your art and design skills to create a 3D mountain peak. Can you include some glacial features, like corries and ����ê�ٱ�s, in your design?

Think about what kind of materials you will need.

Here are some guides to help you with design techniques using paper: Design techniques: Paper cutting