They are the gurus of globetrotting, the men who built publishing empires from their adventures and wrote guidebooks encouraging millions to venture further afield. Now the founders of the Rough Guides and Lonely Planet books, troubled that they have helped spread a casual attitude towards air travel that could trigger devastating climate change, are uniting to urge tourists to fly less.
Mark Ellingham, the founder of Rough Guides, and Tony Wheeler, who created Lonely Planet after taking the hippie trail across Asia, want fellow travelers to "fly less and stay longer" and donate money to carbon-offsetting schemes.
From next month, warnings will appear in all new editions of their guides about flying's impact on global warming, along with alternatives to reaching certain places.
But the founders of the UK's two largest travel publishers are refusing to give up flying and admit they are not paragons of environmental virtue.
Asked if he felt guilty about the hundreds of flights he has undertaken, Wheeler -- visiting London on a business trip from Australia -- said: "Absolutely. I'm the worst example of it. I'm not going to stop but every time I jump on a plane I think, `oh no, I'm doing it again.'"
Lonely Planet began when Wheeler and his wife traveled from London to Australia in the 1970s, cobbling together a guide on their way. Six million copies of more than 600 different Lonely Planet guidebooks are sold each year, inspiring backpackers and middle-class tourists to take long-haul flights to exotic destinations.
Both men have also pledged to donate money to the charity Climate Care to offset the carbon emissions of their 650 staff who fly around the world every year compiling and updating their travel books. In Rough Guides, the warnings will come under the "getting there" sections of all new editions and will emphasize alternative forms of travel.
The men accept it is less easy to take an alternative route to Peru, but advise travelers to spend more time in one place.
Ellingham, who produced the first Rough Guide with student friends in 1982 after traveling round Greece, recognized their advice could look hypocritical.
"Like so much in life, it's a contradiction but we are uniquely well-placed to address travelers," he said. "We've got a responsibility to make people aware of the information about climate change so people have a less casual attitude towards flying. We want to show that two companies who are direct rivals feel this is an issue important enough to coordinate and cooperate on."
Both men said they do not mind if their advice discourages people and hits sales of their books.
"I'd rather customers bought one book today than no books at all tomorrow," Wheeler said. "If we do real damage to our planet, we're not going to be able to travel anywhere. We want our kids to be able to travel as well."