It may be called the Yorkshire Three Peaks Challenge, but it probably feels more like three separate challenges. For our partner National Grid, it's one of their biggest fundraising events this year. We caught up with a couple of participants just before they set off.
For Hannah, this was the first event of this kind she'd ever done. And when it comes to training... 'I'm working on it,' came the tentative reply.
As for the day, it's a bit of a slog, to say the least. 'It's an early start,' Hannah tells us. 'We go down on the Friday evening to register about six o'clock, stay in a hostel together and then start early in the morning. And it takes about 12 hours.'
For Hannah the desire to sign up was two-fold. 'I personally just fancied the challenge, and because it's Macmillan' - Hannah has family members who have or have had cancer.
Hannah's colleague Jennifer is also doing the challenge. For her it was a chance to get back to something she used to do in her childhood. 'I miss seeing the picturesque views up the mountains and the feeling of achievement you get from having a long day's walk. I thought this would be a great way of getting back into walking.'
Cancer has also touched her life. 'A number of my friends and relatives have had cancer. I think it's important to support Macmillan so that they can continue to do the fantastic work they do.' And with the aim to raise £25,000, that's exactly what they're doing.
National Grid is supporting Macmillan through a two year partnership that hopes to raise more than £500,000. This will fund more than 2,500 heating grants to help people stay warm without the worry.
So far employees have raised more than £300,000 through a variety of pylon climbs, coffee mornings, head shaves and more.
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