In the 19th century, there were 150 glaciers in Glacier National Park, and now there are just 25. By 2020, even those will be gone, says Daniel Fagre, coordinator of climate change and glacial geology studies in the park.

In order to see some of the last glaciers left in the lower 48 before they're gone forever, Stephen P. Nash of The New York Times took to the trails of Glacier National Park, where he had hilarious encounters with the locals, like this one:

I responded [to a group of hikers coming up the trail] in superlatives, and asked whether folks here talk much about what’s happening with the glaciers.

There was a pause and the temperature seemed to decline a degree or two. “God will take care of everything we need,” one said.

“I don’t think man has anything to do with that,” her friend put in.

The lesson is, when engaging in so-called "last-chance" tourism, don't remind your fellow travelers that they are just as culpable as you are for the eradication of the very beauty they've come for.