Christine Louise Hohlbaum and her husband took their children to Venice when they were 2 and 4 years old. Looking back, she wishes she'd waited until they were a little older.
"It was expensive, they were cranky and we said next time we'd go without them," said Hohlbaum, who lives in Germany and blogs about life as an American stay-at-home mom abroad at
Despite - or maybe because of - the hassles, businesses that cater to families traveling abroad are booming. A 2006 survey of AAA Travel professionals found that 42 percent were booking more international trips for parents with children under 18. A company launched in 2003 called Ciao Bambino customizes upscale family trips to France and Italy and is an online resource for family travel planning. And Disney's family-focused tours, Adventures by Disney, went from two European itineraries last year to eight this year.
Overall, 8 percent of U.S. outbound passengers consists of adults flying with children, according to the U.S. Department of Commerce's Office of Travel and Tourism Industries. But there is serious debate among parents about what age is the right age for children to start traveling internationally.
Maureen Wheeler, co-founder of the Lonely Planet guidebook company, recommends waiting until kids are 3, "when they're out of diapers, when they can eat food, when they can talk." If you're planning once-in-a-lifetime trips, "then maybe you don't start traveling with your children until the age of 7 to 10."
She added: "I started traveling with my children when they were babies and that's just stupid. It was exhausting."
But Wheeler said that even if her children Tashi and Kieran - who are now adults - don't remember their first trek to Nepal, they got something else out of their early travels. "I honestly think that it gave them an attitude for life, because they learned to be very flexible," she said.
Pauline Frommer, the travel guidebook writer and daughter of Arthur Frommer, started traveling with her parents when she was just a few months old. She said her father thinks international travel is wasted on small children because they don't remember much, but she's not so sure.
"Everywhere I go in Europe, I have this sense of deja vu," she said. "Beyond having a strong sense of deja vu, I have many strong memories from my travels. So I know that kids remember more than we think they do."
Continuing the family tradition, she's taken her young daughters to the Dominican Republic, the Czech Republic, Italy, Ireland, Costa Rica and Brazil. This summer, her older daughter will accompany her to China, then the whole family is going to Scotland and Wales.
"Vacation time is often the only time when families get a good solid chunk of time together," Frommer added. "So what are parents with wanderlust to do? Just stick with the tried-and-true theme park and cruise vacations, squelching their own desires to see the world? For many, leaving the kids at home over vacation just isn't doable, financially or emotionally."
Elisa Bernick, author of "The Family Sabbatical Handbook: The Budget Guide to Living Abroad with Your Family," said traveling with children has advantages for grown-ups. Her family lived in Mexico for 18 months, starting when her kids were 2 and 7. "One of the primary benefits was that they were the best little diplomats. Kids were our passports into that world," she said.
One memorable occasion was being invited to dinner by a little girl from her daughter's class. "The dinner turned out to be cactus tortillas - nopales - from the back of their pickup truck," she said. "We all hung around, watching the kids run around. We never would have been invited into this kind of situation without the children."
She acknowledged that "if they're 4 or under, they might not remember seeing the Mona Lisa and feel the significance of that in the same way that an older child will. But a 4-year-old or 2-year-old will remember the sense of adventure, excitement, and the growing curiosity all tied to the sense of travel. You're cultivating that adventurous, curious spirit. If your goal is to educate your children about significant things around the world, then perhaps you should wait until age 5. If your goal is simple to have a wonderful adventure with your family, take 'em any time."
Itineraries also make a difference. The first big trip Sunny Kobe Cook took with her stepsons and husband was an African safari.
"That was something even an 8-year-old could appreciate," said Cook, a retired entrepreneur who lives in Seattle. "Later, as they have matured, we have done China and Antarctica. It wasn't until they were in their teens - youngest at 14 - that we did Rome. By then they were mature enough to be awed by the Sistine Chapel and respectful during Mass said by the Pope."
But she added that "not only do people waste a lot of money by bringing children too young to appreciate it - they waste our money and take away from the enjoyment of others by the behavior and coaxing the rest of us have to endure."
Her advice: "Stick to the Disney and Carnival cruises until your kids are old enough to appreciate what they are seeing."
Eileen Ogintz, who writes about travel at TakingtheKids.com just spent two weeks in Europe with a "13-year-old who was only happy when shopping and ice cream were on the agenda."
"Parents heading across the pond have got to be realistic about touring great sites with kids and grandkids," she said. "It will be hot. The kids will get bored and cranky. It's also going to be expensive because of the weak dollar. That's not to say it can't be a terrific experience, especially if you look at some of these places through the kids' eyes, and cut the itinerary in half to allow for plenty of sleep for teens, and playground and swim time for younger ones."