Sixteen-year-old Andrew Hudis was riding on a bumpy jungle road near the Thai-Burmese border last summer, past a refugee camp of bamboo huts enclosed by barbed wire, when he and Philip Carlitz, a classmate at Council Rock High School South, hatched an idea.

They saw the plight of orphans and wanted to help. They decided to raise money by running a marathon, and proposed the plan to David Venning, the driver of the car and chairman of the nonprofit travel company that organized their trip.

He liked the idea.

In retrospect, perhaps a little too much.

"I think he mistook us when we said the word run," recalled Hudis. "We meant run as in run with your feet. He meant run as in operate."

The wiry Hudis had already run four marathons in the United States. And Carlitz, 16, had finished one himself.

But neither had any experience organizing a marathon - especially not halfway around the world.

No matter. The inaugural Tribe-to-Tribe marathon - spanning a scenic, winding course beside the Himalayan foothills in northwestern Thailand - is set for July 5.

And even before the starting gun, Hudis and Carlitz have taken the lead.

They've painstakingly mapped the ideal running route and helped assemble all the necessary amenities: medical tents, hundreds of energy bars, the cooperation of the sometimes difficult local police, and loads of pad Thai for a pre-race "carb party."

They've even enlisted the services of a dozen elephants, which will march part of the course and greet runners at the finish.

There have been obstacles along the way, the biggest among them the recession, which has hampered fund-raising efforts and discouraged potential corporate sponsors.

But Hudis and Carlitz, friends since the third grade, are used to the long haul.

"They're committed," said Venning, 49, who founded the Rustic Pathways Foundation 26 years ago. The travel company offers programs in 18 countries for students, families, and groups, according to its Web site.

With their project, Hudis and Carlitz have solicited donations to help Rustic Pathways build an orphanage in Thailand for 150 Burmese refugees.

"They're idea people, and they follow through," Venning said. "It was great to see these guys - no pun intended - seize it and run."

Run they did, but without letting their youthful ambition stray.

Jeannine Mitchell, Hudis' English teacher at Council Rock High School South, particularly admires his modesty.

"He's not the kind of kid who blows his own horn," she said. "He has the full package: He's intelligent, but he's also socially aware. He's more than just gifted. I think he has a real commitment."

Despite a strenuous workload, the two juniors haven't lost sight of their goal to help some of the thousands of refugees. What they saw while visiting the region last summer both chilled and inspired them.

Hudis and Carlitz were offered three pearls to smuggle a refugee's son over the border into the relative safety of Thailand, Carlitz said. They refused, but only out of fear of being caught.

Hudis, meanwhile, told the story of one orphan who was sponsored by a well-meaning American family nonetheless oblivious to his hardship.

"They took him down to a villa, and for three days, this Thai kid, who essentially grew up in a room of 30, has his own suite in one of the nicest hotels in Phuket," Hudis said. "And every night he sneaks out of his room and goes into theirs, because he's never slept in a room by himself."

In the small northwestern town of Mae Sariang, Thailand, the route comprises three separate footraces: a full marathon (26.2 miles), a half-marathon (13.1 miles), and a 5-kilometer course. Donations will benefit the 17-room Hill Tribe Orphanage being built there by Rustic Pathways.

With the project, Hudis and Carlitz also have other long-distance goals in mind.

Hudis is trying to become the youngest person to complete a marathon on all seven continents. He has crossed North America off the list, with Asia now to follow.

And Carlitz, an aspiring international businessman, has gotten a crash course in overseas management.

But this marathon, they acknowledged, will not be about finishing first.

The teens are trailblazers either way.

"If it took me five hours to finish - if it took me six or seven - I don't think I'd care," Hudis said. "Getting to run it is almost a gift. Why would I want to rush through this?"

Contact staff writer Max Stendahl at 610-313-8207 or mstendahl@phillynews.com.