Austinite West Hansen and David Kelly of California were racing on part of the Amazon River in 2008 when they wondered what it would take to kayak the river’s entire 4,200 miles.

That thought turned into a grand adventure.

Earlier this month, Hansen returned to Austin after four months of kayaking the Amazon from its source to the Atlantic Ocean.

Austin residents Jeff Wueste and Ian Rolls paddled with him for all but the first 500 miles. The trio endured exhaustion, extreme weather, rough waters and a run-in with bandits.

"But the hardest part was being away from my family, from my wife and daughter," said Hansen, who, upon arriving at Austin-Bergstrom International Airport, was cheered by a group of family and friends.

Only eight other people have paddled the Amazon from source to sea, the first in 1985, Kelly said.

Kelly helped plan and manage the expedition, along with a support team of two dozen people, some of whom kayaked with Hansen for parts of the trip.

The journey "has epic magnitudes," said Kelly, who lives near San Francisco. "More people have left our planet to walk on the moon than have paddled the entire length of the Amazon."

"At a time when people say all the adventures have been had, West was interested in exploring what few people had done," Kelly said.

Hansen, 50, is a social worker who has kayaked for nearly three decades but had never attempted a trip this long.

"I’m a pretty average person, and I’ve read books about these incredible, larger-than-life explorers, and it makes me feel good that I’ve been able to walk in their footprints," he said. "It just takes getting out there and doing it, one step in front of the other."

The journey took 111 days (90 of them paddling), from Aug. 17 to Dec. 5, and it bested a record by one month.

The expedition began high in the Peruvian Andes, where the Amazon’s source is narrow enough to step over, and ended in Brazil, where the river runs through the jungle and becomes more than 90 miles wide.

The kayakers faced blizzard conditions in the Andes and scorching temperatures in the jungle. They saw pink and blue dolphins. They paddled through calm waters and surging rapids. They were robbed once by bandits and held a few times at gunpoint. But they also met villagers who offered kindness and help, such as food and shelter.

"We slept. We ate. We paddled. Everything else was secondary," Hansen said. "It was much more difficult the closer we got to the ocean. No one had done it at this time of year, and the tides were much stronger than we expected."

They slept mostly in tents, ate freeze-dried foods and drank powdered mixes added to river water that was run through a filtration pump. Twice, family members met up with them and supplied treats from the United States, such as Oreos and M&Ms.;

The trip cost about $110,000, Hansen said. National Geographic paid about a third and will chronicle the trip in a future issue, he said. He said he, family members and other donors paid the rest of the cost.

Hansen is writing a book about the experience. And he’s already thinking about planning his next river journey — "One that has never been done before," he said — to a place he didn’t want to reveal just yet.