WALKING in a straight line is a piece of cake. Unless that line travels almost 50 miles across the Scottish Highlands.

That’s what two Scots achieved on Monday by walking the longest straight line ever attempted in the UK.

Starting on Friday morning, the pair finished the 78.55km journey – with a total ascent of 5706 metres – on Monday evening.

Trudging through thick heather, steep rocks, forests, crags, gullies, river crossings and waterfalls, Jenny Graham and Calum Maclean eventually made it from the A9 to the A939 through the heart of the Cairngorms National Park.

The pair spoke to The National to explain why they decided to embark on the impressive feat and what they’d learned along the way.

The National: Photograph by Johny CookPhotograph by Johny Cook

“A couple of friends suggested to me I try it. I thought yeah, I probably could do it. Yeah, I'd like to try it. Just to see, setting yourself a new challenge. That was a huge part of it, just to see if it was possible for me to do it,” said Maclean, an outdoors broadcaster at the BBC.

Maclean invited word record-holding Scottish cyclist Graham along for the journey.

The two had barely met before the endeavour but became pals along the way with Graham saying “Calum and I hadn’t spent more than an hour together, then we weren't more than a metre apart for four whole days”.

Graham is not averse to adventure though, holding the world record for cycling around the world faster than any other woman.

But walking in a straight line across Scotland was a different type of challenge for her.

The National: Source: Ordnance SurveySource: Ordnance Survey

She said: “What attracted me to this I think was the simplicity of it. When Calum told me about it it’s one of the things that you can't get your head around, you know, you're like, oh, an actual straight line through Cairngorms. Yay. Sure. That sounds great.

“But's very, very different than anything that I had done before, you know, like completely different.

"I love journeying in the mountains, but we'd always be choosing lovely, sharp ridges and, and, you know, going for spectacular views. So I'd never, I'd never walked anything like this before.

“I just couldn't believe like how rugged this adventure was.”

Despite Scotland’s landscape and weather being less than ideal at times, Maclean says the feeling of endlessness walking in a straight line was one of the hardest things they had to deal with.

The first two days were the toughest, the pair agreed, with moorland making up much of the landscape, while the second half of the journey provided some scenic relief to motivate them to carry on.

In terms of planning, Maclean went for a simple approach, planning point A and B from start to end with the route invented by the Ordnance Survey. He says someone asked what's the longest strict line you could walk in the UK without crossing a paved road.

The route meant neither Graham nor Maclean did not see a single road, an odd experience which led to Maclean kissing the tarmac when he saw it at the end.

In total, the pair completed the walk in 83 hours and 56 minutes and are glad they did it – but don’t see themselves doing it again.

The National: Photograph by Johny CookPhotograph by Johny Cook

“It wasn't a summer holiday. That's for sure. And there was definitely times that you were questioning your sanity for being there,” Graham said.

While Maclean said he would like to alter the next challenge to include different terrains and swimming too.

If you’d like to experience the adventure without taking on the gruelling task yourself, adventure-film production company, Summit Fever Media, intend to premiere a 20-minute film of the longest line project at Kendal Mountain Festival 2021 in November