Good article. Goes into a bit of detail as why these locations and animals are endangered. Also gives an idea as to the cost of traveling there.

"Isn't it ironic that as it gets easier to travel around the world, there are fewer amazing things to see. The earth's most revered marvels are increasingly falling victim to overcrowding, global warming, and untrammeled development. Of course, the rush to see those disappearing treasures means—ironically, again—that they become even further endangered. Climate change and human encroachment are without doubt the double karate chop to many of the world's most special wonders, threatening to KO them for everyone. So while we're suggesting that you put these spots on your must-do list, we also hope you visit them in a low-impact, environmentally sustainable way. And spread the word: With the right kind of attention, these wonders will be around for future generations of travelers..."
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1. The glaciers of Europe
2. Africa's lion population
3. Central America's cloud forests
4. Orangutans of Borneo
5. The Florida Everglades
6. The Taj Mahal
7. Arctic polar bears
8. Great Barrier Reef
9. Louisiana's coastal salt marshes
10. The snows of Kilimanjaro
http://www.msnbc.msn.com/id/25737162/Slide show:
http://www.concierge.com/ideas/activeadventure/tours/2113?mbid=MSNBC