I was asked by a close friend before departure why exactly we were making this journey and the more I thought about a sincere response, the blanker my mind went. Not so good when you are putting your life plus every penny you own behind something. We weren't doing this to raise money for charitable causes and so didn't want to place this falsely at the top of our agenda. I love Brazil passionately and have done since I first arrived there nearly 10 years ago. But why exactly? People asked, and again… I couldn't give a deeper explanation. What had driven us to make such a commitment, and what continued to drive us both so strongly through the tired, low and lonely moments? The biggest journey is indeed 'within' and it seemed that only with time would we begin to unravel the truth.

Our jungle shirts and high-tech quick drying trousers are now stained with green splotches of tropical mould that seem to be slowly morphing from light polka dots into giant blobs. Shirts are split at the shoulders from 2300km of paddling. Last week we paddled into the Amazonian city of Santarém, 125 days into our voyage. But as the mould and rips grow, so does our little line across the map of Brazil.

So much time planning, dreaming and pondering over maps has actually translated to something real and here we are today in the thick of everything we planned and prepared for, not for a moment wanting our lives to be any different. As we plot our daily position, we have shaky waves of amazement at how far we still have to go to get down to the border with Uruguay - another year at least.

There have been moments when things could have crumbled from under our feet and left us reflecting for years to come on our failure, but we have managed to overcome the challenges and paddle on.

We are spending abnormal amounts of time in each other's company and decisions are made several times a day that effect both our immediate safety and the future of the expedition. Two people make for a tricky democracy and with no time to argue, one of us must retreat and try their best not to judge the other in hindsight. An 'I told you so' situation in a tense moment would be enough to pull the rug from under us. ‘Paper, scissors, rock’ unfortunately cannot be relied on for decisions of any significance, but it has helped resolve minor squabbles, such as who gets the crap hammock spot - although Aaron remains invincible at this game and I’m increasingly reluctant to play.

Our 'human-power' had propelled us all the way down from the remote jungle on Brazil's border with Guyana, down a chain of tributaries (Rio Maú, Rio Tacutu, Rio Branco, Rio Negro) and finally onto the Amazon itself. We hope our bodies will continue to perform across the vast distances ahead. Meanwhile, through our increasing experiences with the Amazonian people, known as caboclos or ribeirinhos, the concept of 'human-powered' travel took on a new dimension. Without the friendship, food and shelter offered by these fellow humans, we could have spluttered to a stop. We’d met a bad apple or two, and are likely to meet more in the future, but this doesn’t taint what has so far been a rhythm of new friendships.

Countless nights we paddled up to stilted riverside shacks with a storm and darkness rolling in, our safety relying on the understanding and kindness of the strangers gazing hesitantly out of the shutters at us. If they were spooked by the two grubby gringos in a strange vessel, we’d be left paddling through the night until we found a place to camp, risking running a nasty storm in the dark in our small canoe and being easy prey for the nocturnal river pirates.

If they welcomed us in, we’d have a dry night, spent eating and exchanging stories by candlelight, being sent off with sad goodbyes the next morning or often few days later. They would rarely accept money for the cargoes of passion fruit, pineapples, fish, wild honey and farinha that they filled our canoe with. Luckily and in testament to the Brazilian spirit, we were nearly always welcomed.

“Meu Deus! You’ve paddled all the way from there?!” It was the story of our adventure that opened the doors for us, and living on the river we had more in common with our hosts than we had imagined.

Human-power in this form of kindness and understanding did not only come from the caboclo river folks, but from global strangers who have donated to our expedition via our website. Arriving in a town to check our email, our hearts would be warmed to find donations from mysterious places like Bulgaria or the Federated States of Micronesia.

It all started to make more sense. To us, the true beauty of this human-powered travel lies in its inherent slowness and the intimate world of encounters it opens up, and not in simply going as fast as physically possible from A to B with X amount of extreme drama in between and Y amount of world-records at the end. It presents an infinite universe of stories to explore in a world where apparently there is not much left to discover in the classical sense. And hopefully it gives us the opportunity to share and inspire a few people along the way.

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