Gary Barlow, Chris Evans, James May and Brian Cox have set off from Lands End in a pink Rolls Royce raising money for Breast Cancer Care.
The challenge will see them driving from Land's End to John O'Groats in a bespoke pink Rolls Royce Ghost.
They want to try and raise £1 million in 24 hours.
The four celebrities will stop off in Bristol as part of their trip.
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A young man's fallen to his death in a student block in Plymouth in what is understood to be a tragic accident.
Devon and Cornwall Police are searching for missing man James Moore, 59, from Crediton.
You will need to spend all of your old round pound coins before October 15 this year - after that they will no longer be legal tender.