GREENWICH, England – He was a young man then. Fresh out of London University, Jason Lewis was running his own window-cleaning business and playing in a grunge rock band when his friend Stevie Smith was struck by the terrifying thought that the prime of his life would turn out to be less than it should.

“What I see, day after day, are captured lives, half-lives, dedicated to a mirage of fullness that never comes,” Smith would explain later. “My greatest fear is of mediocrity and of a slow, unremarkable acquiescence to society.”

Come with me around the world, Smith told Lewis. We’ll circumvent the globe like Magellan rode the wind, but we’ll do it under our own power: by bicycle, pedal boat, kayak, roller blade and our own remarkable feet.

“When do we start?” Lewis replied.

The answer to that question was July 12, 1994 – more than 13 years ago.

One of them finished Saturday, but it wasn’t Smith.

Leather-faced, thin, weeping and now 40 years old, Lewis peddled his boat up the Thames to the Prime Meridian here — 46,405 miles, and yet exactly to the spot where he and Smith had started. Smith, who dropped out five years into the journey, stood back quietly among the cheering spectators, getting jostled by the back end of TV cameras.

Along the way, Lewis capsized in two oceans, was chased by a 17-foot crocodile in Australia, suffered from two bouts of malaria, underwent surgery for two hernias, nearly died of blood poisoning 1,300 miles out to sea from Hawaii, stumbled into a civil war in the Solomon Islands, suffered acute altitude sickness while biking over the Himalayas, got hit by a car and broke both of his legs in Colorado, was robbed in Sumatra at the point of a machete and arrested as a spy in Egypt.

He sold T-shirts and did odd jobs to raise money, and then kept going. He fell in love, but said good-bye and kept going.

“Thirteen years, coming to an end. It’s been a big, long journey. It’s good to be back,” Lewis said simply as he pushed his 26-foot-long pedal boat, now resting on a trailer, across the cobblestone courtyard outside the Greenwich Royal Observatory.

Although it is still in dispute, Lewis and his Expedition 360 team believe it to be the first true human-powered circumnavigation of the globe, a voyage that spanned 37 countries both north and south of the equator and ended at the point where longitude and the Earth’s time zones begin.

Standing opposite Prince Richard, the Duke of Gloucester, a patron of the voyage who christened the boat “Moksha” (Sanskrit for “Freedom”) Lewis was clad in canvas sandals, bicycle shorts and an old wind-breaker.

“It gives me great pleasure to inform you,” Lewis declared, holding aloft a magnum of Taittinger Champagne , “that as of this moment, the world has been circumnavigated using only human power.”

Lewis left Greenwich 13 years, two months and 23 days ago, having spent a grand total of three days crewing on a sailboat and no more than three miles at a time on a bicycle.

He and Smith crossed English Channel, bicycled to the Portuguese coast; spent 111 days crossing the Atlantic to Miami in the pedal boat (at a speed of 2 to 4) knots and spent a year roller-blading across the U.S., where Lewis was waylaid for several months recuperating from the car accident in Colorado. They set off early in 1997 by bicycle for South America, intending to cross from Peru to Australia. They made it as far as Honduras, but unfavorable currents forced them to reverse thousands of miles to San Francisco and pedal to Hawaii first.

It was in Hawaii, five years into the journey, that a no-longer-aching-for-adventure Smith threw in the towel.

Lewis kept going. While later he would bring in crew members to help, he pedaled alone for 72 days across the Pacific.

“I just let the boat drift when I was sleeping,” he said, which caused a problem near the equator. “I’d pedal in the day and go to sleep, and wake up in the same space where I started the previous day,” he said. “That was probably the most demoralizing part of the whole expedition.”

He arrived in Australia $40,000 in debt and spent more than three years fundraising and working with local schools while traversing the outback by bicycle. Lewis then pedaled his boat to southeast Asia; bicycled through China and eastern Tibet to India; took his boat to Djibouti in east Africa; bicycled and kayaked through Africa and Turkey; and bicycled from Turkey to France, before setting out one last time on the pedal boat to cross the English Channel and up the Thames.

At sea sometimes weeks at a time, the boat carried freeze-dried rations in one end, a small sleeping compartment known as “the rathole” in the other, and had an onboard desalinator for making drinking water.

“The idea was to be able to travel through countries, meet people, experience culture. I suppose it was part physical challenge and part the human-powered element, to be able to travel slow enough to experience culture at a very grass- roots and grounded human level,” Lewis said in a telephone interview from Belgium last week before launching the final leg of his trip.

“I loved the Atlantic,” he said. “Being away from the clutter and distractions of normal day-to-day life on land,” he said. “I found this sort of Zen-like state being on the boat, doing one thing at any one time well, rather than a lot of things badly, like one does on land.”

In addition to financial help from more than 1,800 individual contributors, Lewis earned money by odd jobs including working on a cattle ranch in Colorado and a funeral parlor in Australia. He sold expedition T-shirts for $20 apiece. One company donated the 340 roller-blade wheels he chewed through crossing the U.S.

Lewis’ father, retired army Col. Sebert Lewis, meanwhile, helped with logistics and plotted his son’s position on navigation charts with a fix Lewis would send each day by satellite communication.

“I’d get a message: “All OK.’ Then latitude and longitude, then date-time-group,” the elder Lewis said.

Later, Lewis and his traveling companions began posting diaries, photos and video to a blog.

“I’m hugely relieved that this whole thing is over. And sad in a way, that a whole chunk of my life will be missing – that which is the daily and nightly anxiety over what’s happening to the boy,” his father said. “It’s been like a military exercise for 13 years. The dining room table will no longer be covered with charts and maps and situation reports, looking after Jason in some far distant clime.”

Lewis now faces establishing his feat as a record.

There is a challenger: Canadian Colin Angus claims to have completed the first human-powered circumference last year, in 720 days. Lewis says Angus’ journey was much shorter, and spanned only the northern hemisphere; Angus says Lewis had help pedaling the boat and had to double back on one of his Australian legs, disqualifying him.

Two Americans have separate expeditions under way now.

Lewis also plans to write a book, to give a series of talks and help develop educational materials stemming from the trip. In between, he hopes to find the kind of ordinary life he and Smith once scorned.

“On the trip, I fell in love, deeply, a couple of times,” he said. “I remember leaving this girl I was absolutely in love with, on the beach there after Baja. We had just finished crossing the Sea of Cortez to mainland Mexico, and she had to go back to San Francisco.

“I remember the day, I remember it like it was yesterday. We never saw each other again,” he said. “I remember just riding my bike, going into this head wind in Sinaloa, thinking what in the heck am I doing? It was probably one of the points where I questioned the sense of going on, where everything was telling me, you’ve got this woman you love, why go on with this crazy trip?”

“For some reason, maybe it was pride, I always felt the need to go ahead and finish it.”

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