THERE'S a reason Steve Backshall, pictured right, is grinning from ear to ear.
The wildlife presenter and adventurer, best known for his popular Deadly 60 series, finally got to go on the expedition of a lifetime.
After years of planning he embarked on a mission to become the first person to navigate the full length of the Baliem River in the wilds of West Papua, Indonesia.
"I first went out to this region 20 years ago and did a big expedition there; it blew me away," he tells The Guide.
"It was the most I've felt like an explorer on the whole planet. I came across this river and it's enormous in its scope. I hatched this grand plan to paddle it from source to sea. After years of trying and failing to get this expedition off the ground, the BBC gave me the green light to plan it two years ago.
"To me it's one of the grandest expeditions left on the planet to do."
And, of course, he had a camera crew in tow to capture every wet and wild moment of the 500km journey.
It took Steve and his expert team of kayakers a little more than a week to navigate the most dangerous stretch of rapids in the Baliem Gorge.
"The river starts in the highlands and then drops down into a gorge filled in with some of the most intense white water on earth," he says.
"Once you are in there you are completely committed. It's 80km of Class V white water (the second most dangerous rating for rapids), which is very intimidating.
"The whole thing was frightening but grand and beautiful."
Days of battling the churning white water pushed Steve to his physical limits.
"The guys I was with were some of the best paddlers in the world and even they were finding it hard," he says.
"I'm a generalist; I climb, cave, dive, kayak. I'm nothing like up to their standard. There were periods where I was just broken, but you have to get back in the boat because you've got to get out of there.
"You can't even make satellite calls. You do feel very far away from the modern world; I love that."
Luckily the majority of the expedition wasn't as intense.
On shore he met the region's notorious cannibal tribe, learned how to trap saltwater crocodiles and searched for the beautiful and elusive birds-of-paradise, one of David Attenborough's favourite subjects.
"The wildlife in Papua is quite similar to Australia. You get big crocodiles, tree kangaroos, possums, lizards and snakes, but the thing that stands out is the birds-of-paradise," he says.
"They are usually impossible to find but there are some places in the mountains where they are common.
"There are some areas of the gorge where there's no way you could walk there (from the outside). We went into some cave systems where you can put your hand on your heart and say 'no one's ever been here before'. I think that's very powerful in this day and age."
Steve Backshall's Extreme River Challenge airs tomorrow at 6.30pm Qld, 7.30pm NSW on Foxtel's BBC Knowledge channel.
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