By Judith Newman Rennie Dyball Thailan Pham Sue Corbett
June 09, 2008 12:00 PM

Disappearing Destinations authors Heather Hansen and Kimberly Lisagor recommend 37 locales to see before they’re spoiled—and ways to help in each. Three of their favorites:

1 EVEREST NATIONAL PARK Lakes formed by melting glaciers may wash away villages in this Nepalese sanctuary. Go responsibly—book through ecotourist groups like KarmaQuest—and give back by contributing to WWF Nepal.

2 GALAPAGOS ISLANDS With large cruise ships now allowed in, the ecological balance is threatened. Travel on a small vessel, use local guides and keep a respectful distance from the wildlife.

3 AYSEN, PATAGONIA A fly-fishing mecca and “the coolest place I’ve been,” says Lisagor, Aysén may see its rivers dammed by a power company. You can support groups trying to stop it (the Sierra Club is one).