The Matterhorn was conquered on 14th July 1865 by Edward Whymper. But four men died on the descent. Damian Lewis stars as Whymper, forever tormented by the tragedy.
Jonathan Myerson's drama speculates on what went wrong and why. The climbing team were roped together on the way down but at least two were inexperienced and - for reasons never fully explained - attached together with rope that was unsuitable for holding the weight of a man.
A swift inquest was held and Whymper was exonerated. But some people never forgave him - especially the 8th Marquess of Queensbury, father to Douglas Hadow, one of the dead.
Produced and directed by Clive Brill
A Brill production for BBC Radio 4.