Take some soil from deep down in the garden, add some water and straw and stamp on it until it's mixed. Build it up layer by layer and you end with a rock-hard structure made from cob.
A few centuries ago plenty of houses were built from cob and they're still standing, but now two artists are reviving this old tradition but with a modern twist on cob, making huge sculptures and even a bus shelter for the Eden Project.
Claudia Hammond went to Devon to meet Jill Smallcombe and Jackie Abey to see just what the possibilities are working with mud.
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