“Lonely Planet is the bible in places like India,” Mark Ellingham, the founder of Rough Guides, the cheeky British series, says. “If they recommend the Resthouse Bangalore, then half the guesthouses there rename themselves Resthouse Bangalore.”

The series’ authority is such that the team accompanying Jay Garner, the first American administrator of occupied Iraq, used “Lonely Planet Iraq” to draw up a list of historical sites that should not be bombed or looted.

The writers Marianne Wiggins, Jilly Cooper, and Pico Iyer have used Lonely Planet guides to immerse themselves in the feel of a far-off locale for novels set in, respectively, Cameroon, Colombia, and Iran.

And, in perhaps the greatest tribute, the Vietnamese have begun to manufacture ersatz Lonely Planet guides to complement their line of fake Rolexes.