Montana is warming at a rate that's twice as fast as the national average. Rising temperatures and an increasingly early onset of spring threaten to thaw the giant glaciers that have made this 1 million acre park a scenic destination for hiking, fly-fishing, and cross-country skiing. According to The Guardian, only 26 of 150 glaciers that were present in the park in the 19th century remain today, and all the remaining ice formations are expected to melt within a few decades.
Related: 20 Destinations for Plant Lovers Across America