IN HIS quest to paddle the length of the longest river in each continent, Mark Kalch has encountered everything from deadly whitewater rapids to trigger-happy cocaine traffickers.
But don't tell his mum.
The former Sunshine Coast man, who was recently named one of the world's 50 Most Adventurous Men, has completed a solo trek the length of Iran from north to south, paddled the length of the Amazon with two companions and completed a solo paddle the length of the Mississippi in the USA.
Last year he conquered the Volga, Europe's longest river, alone in 71 days.
The 38-year-old admitted he thought his "number was up" several times during his expeditions and he has often had to add a "filter" into the news he sends home to mum Donna in Coolum.
"Sometimes I think it is a case of the less she knows the better," Mr Kalch admitted.
"If things go bad I wait until well after to let her know."
Mrs Kalch said she could not help but worry, but there was a line.
"You don't want to spoil it for your children do you?" she said.
"I know a lot of things after the event and I am very worried about that (planned future) Nile adventure; I don't know how I could get him out of that."
The Nile, China's Yangtze River, Antarctica's Onyx River and our own Murray-Darling River are the final four challenges on Mr Kalch's 7 Rivers 7 Continents agenda.
The marvel of Skype means Mrs Kalch has been able to get to know her grandchildren and even chat to Mark when he is in the middle of an adventure.
Although Mrs Kalch is proud of her son's achievements and making it on to the adventurous list along with idols Mike Horn and Laird Hamilton, his children are not too excited by it all.
"They know that daddy goes off to paddle these very long rivers for months at a time in other countries," he said.
"They did get to watch me fight in one of my Brazilian Jiu-Jitsu competitions and they were very excited to see me win gold.
"They thought I was a bit of a hero until something more exciting came along, like lunch."
Mr Kalch said he was inspired to lead a life of adventure by his father Franz, who passed away when he was 14.
"My dad emigrated to Australia from Austria and built his own boat and sailed it halfway around Australia," he said.
"He was fascinated with everything about our planet, its people, geography, everything.
"Our bookshelves growing up were lined with every issue of National Geographic Magazine.
"His wonderment, I really think, instilled in me a desire to head off to some interesting places and find out what they are really like."
Mark is still deciding whether the 6300km Yangtze or the 3370km-long Murray-Darling will be the next river ticked off his list.
"Both are appealing for very different reasons," he said. "I am looking forward to paddling across my own country for once."
2007-2008: Paddles the Amazon (6937 km) in a whitewater raft with two companions.
2010: Walks across the entirety of Iran, alone. "I was tired of paddling," he says.
2012: Paddles the length of the Mississippi alone, starting at the source of the Missouri and ending in the Gulf of Mexico (6275 km).
2014: Paddles the length of the Volga, Europe's longest river (3645 km) in 71 days, most of them in central Russia.
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