Most people who take on the National Three Peaks Challenge do so on the middle of summer, when the weather is warmer and the daylight hours are long.
But for two former soldiers from Cumbria, the reverse will be true as they set to take on Ben Nevis, Scafell Pike and Snowdon at Christmas to raise funds for the charity Help for Heroes, the Westmorland Gazette reports.
Darren Slater and Ewan Murdock will be heading up Ben Nevis in darkness on Christmas Eve, a task that may be helped by the use of thermal underwear
and warm winter jackets
The pair will then climb Scafell Pike in daylight on Christmas Day before another night ascent up Snowdon.
Local businesses have been helping the pair, including the provision of a GPS
to help navigation in the dark.
Ben Nevis may be particularly treacherous in the winter darkness, as it has a number of sheer cliffs with overhanging cornices.
Those who have climbed it in summer may note Scotland's highest mountain often holds snow even in summer.