Three teenagers undertook a gargantuan challenge to raise money for charity.

Samson Marshall and Tallulah Chalstrey from Dorchester and Lily Holmes from Weymouth, all three of whom are 17 years old, took on the Three Peaks Challenge to fundraise for The Brain Tumour Charity.

The challenge involved climbing the tallest mountains in Wales, England and Scotland – which are Snowdon, Scafell Pike and Ben Nevis respectively – all in the space of 24 hours.

Tallulah said: "We decided to do the Three Peaks Challenge because it is a well known challenge. It is particularly known for being tough and very hard to compete in the 24 hours.

"A lot of the people who take on the challenge do it through the military, so we thought we would try and take it on and see if we could do it at the age of 17.

"We were nervous on the journey up to Fort William. However, we were excited as well. We were all so full of emotions because we just didn’t know what to expect."

The trio chose to raise funds for this particular charity as they had all lost people close to them through a brain tumour.

They started with Ben Nevis at 3.30am, which they completed in four and a half hours.

Despite heavy traffic on the way and rainy weather on the climb, they managed to take on Scafell Pike in three and a half hours.

The conditions got even worse in Wales, where visibility was poor as they climbed Snowdon at 11pm.

Their efforts raised more than £2,750 for The Brain Tumour Charity.

Tallulah said: "Brain tumours are the biggest cancer killer of people under 40 and require a lot of research as the brain is so complex. Only 2 per cent of the money raised for cancer research goes towards finding a cure for brain tumours.

"The Brain Tumour Charity was started by the former international rugby player, Lewis Moody who generously sent us a good luck video message of support which was gratefully received during the challenge.

"50 per cent of the people that work there have experienced a loss of someone to a brain tumour or have had a brain tumour them self.

"We would like to add that we are not stopping here. We have many more challenges and fundraising ideas to come."

For more information about the charity, visit thebraintumourcharity.org