TARKA L'Herpiniere and Katie-Jane Cooper's journey across the Southern Patagonian ice cap is an epic 21st century love story.

The adventurous duo made national headlines as the first people ever to attempt a crossing of the South American region — and their story went global when his marriage proposal at the end of their trek was broadcast around the world.

The full-time expeditionists from Clayhidon, near Cullompton, chose the ice cap because they were adamant they wanted to break new ground. In the end, though, it was the ground that broke them.

"There aren't many things in the world that haven't been done," said Kate.

Tarka added: "No-one had ever successfully made it across from north to south without support."

So Katie, 29, and Tarka, 28, had made their choice.

But just days into their trip, they became tent-bound for five days in one of the most treacherous spots. And when their tent was destroyed, it became a race for survival. Katie said: "We had constant winds in excess of 140kph and snow was reaching the height of the tent every seven hours. On the fifth day, the tent was ripped to shreds."

Tarka and Katie's decision to abandon the expedition didn't mean they were suddenly safe.

Tarka continued: "It then becomes all about how to survive and how to get through — the next few hours would determine whether we'd live. During this time Katie got snow blindness and I got frostbite and fell down numerous crevasses. The helicopter couldn't land on the ice so we had a five-hour climb back up the glacier we'd just come down.

"It is like the porch between the gateway of heaven and hell. It's beautiful when the sun shines, but that's rare and usually the weather is horrific."

But they can't wait to get back there!

"The moment we knew we weren't going to make the end, we both said we have to come back!" said Katie.

"If you fail at something there's a drive to want to go back and complete it.

"Sometimes that drive is more than the pain you've suffered.

"Plus we know we could have made it physically and mentally, but this time it just didn't happen for us. Knowing that makes us want to go back. And its also easy to forget just how bad it is!"

Their next expedition, One World, is set to be the biggest and most challenging yet — a three-year, 30,000km trip navigating the globe on its polar axis, from one geographic pole to the other.

Tarka said: "The way we make a living is through corporate inspirational speaking at schools — so we have to do something inspirational to speak about!"

Katie added: "Some people think we're trying to raise money to do what we want to do — but no one gives you money for nothing.

"Our sponsors expect an investment, so when we get back we're completing a business deal, doing internal and external marketing and doing inspirational speaking for the sponsors. It's a constant business."

Katie grew up in North Devon but moved to the Blackdown Hills at 14, becoming an exceptional horsewoman and winning several national eventing championships.

After graduating from the Royal Agricultural College in Cirencester with a masters in rural tourism she spent three years modelling and travelling before her life changed forever when she met Tarka.

He grew up in France, where he enjoyed adventurous sports, including rock climbing and ice climbing. He moved to England and later studied at Cheltenham College before getting a degree in industrial design at Brunel University.

He was the second person in history to attempt to trek to the North Pole and the South Pole, solo and consecutively.

Katie and Tarka met while Katie was modelling in 2005 and she joined him on a 4500km trek of the Great Wall of China in 2007.

Katie explains how she abandoned the glamorous world of modelling for life as an expeditionist. She said: "I was as girly a girl as they came — I'd cry over a broken acrylic nail, all typical modelly things.

"Then, on the first expedition, I was very ill and lost an inch in height through spinal compression because of the weight of the pack.

"It was incredibly tough but I learned so much about how much a human can push themselves, and I came out a completely new person.

"It helped me realise all the things that are possible.

"When I met Tarka he opened so many doors to things I never even thought about doing.

"My love for travel and seeing parts of the world that no one ever sees means I'm willing to have a go at these things and train hard for them."

Tarka's proposal to Katie marked the end of their adventure on the ice cap and although Katie knew he was carrying the ring with him, it still left her tearful and speechless.

The media had already jumped on the bandwagon and Tarka's proposal was reportedly heard by more people than any other this century — the podcast went out live across the world.

Tarka said: "Originally I planned to ask Katie only if we successfully completed the trip, but the skills and characteristics she displayed to survive and get off the ice were the kinds of characteristics you can build a long and healthy marriage on."