Mark Kalch tends to joke about his little-known life as an explorer as he talks to Viv Hardwick about being selected to give this season’s Royal Geographical Society lecture at Darlington.

"Who the bloody hell is Mark Kalch? Never heard of him,” is the made up quote attributed to Sir Ranulph Fiennes, explorer and adventurer, on the website of an unknown 33-year-old who has already visited 40 countries and just walked across Iran.

“I had no great desire to be a TV star, but these days the sad truth is that unless you are on TV, not that many people care however many expeditions you have. As a means to an end TV would be good,” says the genial Australian who has been asked to give The Royal Geographical Society talk at Darlington Arts Centre on Tuesday.

His audience will learn that the man who has spent the past 12 years trying to become a full time adventurer and explorer survived a 60-day, 1,000-mile trek across what is considered to be one of the most unfriendly countries on earth for Westerners.

Armed with just a map and compass, Kalch walked from the Azerbaijan border with Iran to the Persian Gulf and probably came out in one piece because he posted nice things about the country on the web.

“It was always in the back of my mind that I might be arrested on trumped up charges, but I’d spent around two years planning and researching my visit. If you’re a tourist they don’t seem to hassle you, but Iran is a funny place so I didn’t take a hand-held GPS which was fortunate because there are a lot of military bases in the mountains.

If I had been found with a lot of maps and a GPS there would have been a lot of questions asked.

“My host was the Alpine Club of Iran which is a highly respected group and gave me contacts within the Ministry of Cultural Heritage. One of my first website posts was about Tehrain where I said the metro system is better than the tube in London and one of the chaps from the ministry read this and got back to my friends and said ‘we approve of this guy’. I made a point of not commenting on the politics, because that’s a good way of getting kicked out. I just wanted to meet the people and I stayed with a different family every night,” Kalch says.

Even so there were a couple of times in the mountains where he came close to getting completely lost and was haunted by doubts about taking the wrong direction “I took a lot of footage in Iran, but because it was a solo trip it’s sometimes a little difficult to get decent shots. So a lot is of me holding a camera to my face and that is an accepted thing, but that will depend how interesting that is to the largest possible audience. It is a niche market what I do. So this might end up as short clips for on-line use,” he explains.

Footage from his amazing 2008 three-man raft ride down the Amazon, from it’s dangerous source in Peru, is still being turned into a film.

“I’m hoping it will be screened in Australia where the rest of the team are from and then be shown on National Geographic and Discovery on cable TV.”

THE raft overturned at last four times a day in the early stages of the Upper Rimac of Peru and it constantly went through his mind that it was only his kayaking and white water skills that were keeping him alive.

“There were rapids where, if you got it wrong, it was almost 100 per cent certain you would die. I kept thinking ‘was it our skills or just luck that stopped us from being killed?,” he says “And if it was luck, how long would it last? It was so isolated that if one of us did get injured there was no option of calling in rescue.”

The trio’s flimsy raft was shot at three times, twice by the region’s prolific drug smugglers and once by the army who thought they might be drug dealers masquerading as tourists. “We knew it was a major cocaine producing area, but when we did get shot at it seemed to be more of a warning basically because they move their product at night-time.

“They knew we were adventurers, but then we got shot at by the military who weren’t quite so backward and opend up with automatic weapons over our heads.

“These military guys just wear shorts and carry a gun, so when you see them you can’t decide if they are military or bandits.

They just did a rudimentary search of the boat to make sure we weren’t moving cocaine and let us go,” says Kalch.

Other expeditions have taken him to Everest, North Africa and Ethiopia’s Omo Valley, Peru, East Africa and to Australia’s outback and the forests of South-East Asia.

And the London-based adventurer’s advice to others who want to follow in his footsteps?

“This is a very difficult profession to be in. I basically work from my laptop and if I’m not working on an expedition then I’m looking for a potential lecture date or a magazine commission. Otherwise I don’t get paid.

“So it is a difficult thing to do.

A lot of people align themselves with a charitable endeavour, which I fully agree with, but the first question a lot of people ask me is ‘are you doing if for charity’. But I don’t see the correlation between me climbing a mountain and helping cancer research or feeding kids in Africa.

“That’s not because I’m a mean person. Does someone go to an accountant and say ‘are you doing this job for charity?’.

No they are doing it because they are a professional.”

■ Walking On A Dream: On Foot Solo Across Iran, Darlington Arts Centre, Tuesday, 8pm. Tickets: £10.50.

Box Office: 01325-486-555