Some people dream of touring ancient ruins, modern cities or the great art museums of the world.
Sarah Damsky, a 30-year-old social worker now living in London, loves doing all those things on vacation, but often returns exhausted.
So when Damsky went on a yoga retreat to Vieques, Puerto Rico, she found she was "refreshed" and better able to tackle her everyday life.
Damsky is among a group of travelers who don't just look to sit on the beach -- although there can be plenty of that too -- but to be active and learn something new and healthy while on vacation. Some women on her trip converted to vegetarianism after enjoying a week of well-prepared meatless meals. (Damsky was already one.) Most travelers returned with new friends and new knowledge that they have since incorporated into their everyday lives.
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"You come back from the yoga retreats refreshed," she said, adding that she learned, for instance, "the benefits of taking 15 minutes to meditate in the morning before checking Facebook."
Heath-focused trips can teach travelers how to relax, how to eat better or even lose weight.
Trip operators say that people today are seeking more out of their vacations. They aren't just looking for that postcard-perfect picture but also a life-changing experience, something to better themselves when they are back home or in the office.
There are countless yoga retreats from the mountains to the Caribbean to Mexico. But Sidney Pinkerton, manager of 7 Centers Yoga Arts in Sedona, Ariz., says there is nothing quite like the desert.
She calls Sedona "a very magical place" and has seen a "tremendous increase" in the number of people looking for retreats. (Her 30-day programs tend to focus more on people looking to earn their instructor certifications, although there are shorter classes available.)
"People are looking at their lives through a different lens these days and looking for things that are not just good for them but good for the planet," Pinkerton said. "Nature is the best soother and can help put things back in perspective."
Donna Sewall Davidge owns Sewall House Yoga Retreat in Maine with her husband Kent Bonham, the chef and resident musician.
For 13 years they have been mixing yoga instructions with hikes, bicycling and kayaking from their 1865 bed and breakfast. Part of their job involves teaching meditation and yoga techniques. But they also offer three very healthy vegetarian meals a day.
"People often think vegetarian has to be complicated or boring," she said.
Rates range from $135 to $210 a night, depending on one's length of stay and the number of people in a room.
Davidge said a lot of their success has to do with the setting. The house, which belonged to her great-grandfather, sits on the edge of a state park. It hosted a young Theodore Roosevelt.
People who are changing careers or have recently lost a job will often come to such retreats to gain perspective, she said. One woman came to Sewall House after leaving a job in publishing. She now works at an orphanage in Cambodia.
"A lot of times when people are looking at 'What do I want to do with my life?' they go on healthy vacations," Davidge said. "They decide they don't want to just sit on a beach and drink margaritas and come back feeling worse than when I left my stress-filled life. They just want to feel better when they come back from vacation."
Dr. Mark Liponis, the medical director of the luxury Canyon Ranch spa resorts, said that in just one week people can't really become healthy. What they can do is head home with tools to continue a healthy lifestyle.
Canyon Ranch guests are required to stay at least three nights to help immerse themselves in the program. They can choose medical evaluations, nutritional classes or just relax at the spa.
"Some of the best classes that people come to are the cooking class," Liponis said. "It's not actually healthy unless you make it part of your life. You've got to be able to incorporate what you learned into your daily living. That's the trick."
For instance, to relieve back pain, a lot of guests get massages, but they also learn stretches that they can do at home to prevent future pain.
"They don't realize that all they have to do to keep from getting back pain is to do the 10 minute stretches when they get up," Liponis said.
Other lessons include coping with stress and teaching how to be satisfied on smaller portions of food.
"That's a big discovery for people," he said.
Clients include a man who weighed more than 430 pounds and lost 175 of them in 20 weeks. Other visitors are people "who just can't take off that last 10 pounds."
Besides losing weight, Viskovicz said, people get to relax on the beach, swim and go kayaking.
Many, he said, tell him, "This is the first vacation that I've ever come on where I don't need a vacation from the vacation."
The residential program starts at $2,450 a week for a shared room and focuses not just on eating but on social behaviors and mood. There are individual and group therapy sessions and training about nutrition and proper meals.
"We're doing things to make people healthy for a long time," Viskovicz said. "It's really getting to the source of the problem. If you let yourself gain 200 pounds, there is a bigger problem there."
"We're not a spa," he said. "People get ten times more results at our place but our program is more difficult."