A scene in the documentary "Gringo Trails" shows the litter-strewn aftermath of a tourists' full moon party on Haad Rin, Koh Pha Ngan, Thailand.
Courtesy Pegi Vail
"Gringo Trails" trail —
Featuring footage from Bolivia, Thailand, Mali and Bhutan, "Gringo Trails" looks at the impact of unplanned tourism growth in developing countries. It's currently showing on the international film festival circuit (see bottom of story for dates).
Courtesy Pegi Vail
Backpacker heaven or just hell? —
In 2011, the former traditional farming village of Vang Vieng (not featured in "Gringo Trails") in Laos, turned into party central when it unexpectedly became the country's hottest backpacker haunt.
Matthew Bennett/CNN
Traveling blind —
Filmmaker Pegi Vail -- pictured here -- says she's surprised how often travelers don't recognize the impact they have. (Photo updated from original version of this story.)
courtesy Pegi Vail
Great Salt Desert, Bolivia —
Developing countries want to preserve their attractions while opening them to tourism. Bolivia's extraordinary Great Salt Desert is an example.
Courtesy Pegi Vail
Travel addict —
Vail (here in Bhutan) calls herself a travel "addict." Experiencing new cultures "expands your relationship with the world," she says.