Four pals will be taking on the Three Peaks Challenge to raise cash for the armed forces charity Help for Heros.
Police officer Ricky Brennan, of Leverstock Green, Hemel Hempstead, will be joining Adam Manning, David Wilson and Gavin Sandford for the feat.
They will set off on Friday and hope to raise as much money as possible.
Ricky, who is also a volunteer with the RAF medical logistics team at the International Air Tattoo, said: “Each and every single one of us know people that are in the armed forces. Everyone is touched by it.”
The Three Peaks Challenge involves climbing the highest mountains of Scotland, England and Wales within 24 hours. They will scale Ben Nevis, Scafell Pike and Snowdon covering around 27 miles.
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