Not many people can say they've been to all seven continents. Far fewer can say they've run marathons in all of them.

Wendy Balthazor belongs to that elite club. Balthazor couldn't have imagined it in 2011, as she milled about the start corrals of the Chicago Marathon, waiting to embark on her first 26.2-mile run.

"I never wanted to do any marathons," said Balthazor, 41, a grants and contracts specialist at the University of Illinois. "My best friend convinced me to run Chicago."

Crossing that finish line made Balthazor a convert. The following year, she persuaded her friend to go to Australia to run a marathon that coincided with a solar eclipse.

"When we were down there, we got to talking to all of these international people who'd run all these great marathons all over the world," Balthazor recalled. "I figured, 'If I'm going to run one on this continent, why don't I do one on every continent?' "

She began building her vacations around 26.2-mile races.

"That way I get to do two of my favorite things," she said. "I get to travel, and I get to run, and I get to do them together."

The opportunities to do just that have never been better. Long-distance runners with wanderlust pretty much sums up the client base for companies such as Marathon Tours & Travel, whose offerings include runs on the lemur-rich island of Madagascar, where most of the course cuts through a national park, and a two-week journey to Antarctica, where marathoners on King George Island might be joined by a few penguins. The company also runs an eight-night excursion in Kenya, featuring game drives, bush walks and a marathon through a Maasai village — some of the proceeds help pay for girls to attend high school.

"The race is a catalyst to going somewhere, but when we get there, our clients want to have an authentic experience," said Jeff Adams, president of Marathon Tours & Travel.

The company sells group packages and individual travel arrangements for a growing portfolio of marathons, half-marathons and other running events near and far.

"Patagonia, Jerusalem, Cape Town and Bhutan will all be new offerings for us next year," said Adams.

"Chicago ends up being a gateway race to running the other majors," he said, referring to the Abbott World Marathon Majors, a half-dozen of the most renowned long-distance races held annually in Chicago as well as Boston, New York, London, Berlin and Tokyo. "And once they've run the other majors, they go, 'That was fun. Now what?' "

"Fun" isn't always part of the experience. Balthazor's most recent 26.2-mile race followed the Inca Trail to Machu Picchu in Peru. The up-and-down terrain was both beautiful and brutal, with runners reaching an elevation of nearly 14,000 feet at the ominously named Dead Woman's Pass.

"Physically, it was the most difficult run of my life," she said. "You do three mountain passes in the middle of a marathon, and the whole thing is basically stairs."

It took her nearly 13 hours to finish, compared with the 4 hours and 12 minutes it took her to do Chicago.

Balthazor also has run the Great Wall Marathon in China and the Big Five in South Africa, where "they had rangers with guns on the course in case the animals got too close," she said.

Some destination marathons skew more on the fun side than others, with France's Medoc setting the bar — literally, with wine at the water stations. Tipsy runners sporting elaborate costumes fuel up on fresh-shucked oysters and croissants as they make their way through Bordeaux.

"If you're trying to run it fast, you're missing the point," said Nick Bensen, 55, president of the Oak Park (Ill.) Runners Club.

Bensen has also run marathons in Italy, as well as London, Ireland, Paris, Stockholm and Athens, where the course begins near the town of Marathon, Greece. Runners follow in the legendary footsteps of Phidippides all the way to Athens, where they finish in the marble Panathenaic Stadium, home to the first modern Olympic Games in 1896.

Bensen's wife, Geri, runs with him. "We sort of combine vacations with marathons," he said. "We run at the beginning of the trip and see the country afterward."

"When you put that bib number on, you're no longer a tourist," he added. "You're a participant."