SHANGHAI - Three Swiss nationals chose the hardest way to get to Shanghai from Zurich, the financial center of their country.

They undertook a 12,000-km bicycle trip, which took them four years to complete.

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Graziano Gervas, 51, Beat Fey, 47, and Matthias Dudler, 38, finally arrived at the Swiss Pavilion in the Expo Garden on Wednesday.

The adventure kicked off in 2006, after the three friends found themselves obsessed with the idea of cycling from Zurich to the Red Square in Moscow, Russia's capital.

After months of serious training, Gervas, Fey and Dudler set off on their 14-day cycling expedition to Moscow.

"Riding a cycle into Moscow is like climbing a really high mountain. There was a huge sense of achievement - a feeling of having accomplished something mythical," Fey recalled. "That's when we decided to do one leg each summer, with Shanghai as our goal in 2010."

The whole journey from Zurich to Shanghai was divided into a leg every year.

All of them have full-time jobs - Gervas is a consultant at IBM, Fey is a management consultant and Dudler an assets manager - so taking a vacation for months at a stretch was out of the question.

After the first leg to Moscow, they cycled 3,400 km from Moscow to Novosibirsk in 2008, then from Novosibirsk to Ulan Bator, the capital of Mongolia, last year and finally, from Ulan Bator to Shanghai.

Raising money for SOS Children's Villages, a non-governmental international development organization that has been working to meet the needs and protect the interests and rights of children since 1949, is another reason they undertook the trip.

According to reports, they've raised 80,000 Swiss francs ($76,067) so far. The money has already been forwarded to the SOS Children's Villages in Russia, Kazakhstan and Mongolia. The SOS Children's Village in Tianjin will also receive part of the collections soon.

"The teamwork we generated and meeting lots of new people was the most exciting part of the journey," Gervas said. "Of course, another stimulus to keep pedaling was the idea to help children in need."

At the moment, the three adventurers haven't decided when and where their next journey will begin, but they're certain they will pedal out somewhere again.

"The motivation is there in your own mind," said Fey. "Success comes when you break out of your comfort zone and knock down those old barriers, again and again."