Do you like running off the beaten path or testing the real limits of your endurance? Do you like running up and down mountain trails where the air is thin? If so, then this is the place for you. Even ...

This story appears in the February 2019 issue of National Geographic magazine. In Rocky Mountain National Park, 415 square miles of mountain terrain are protected—but not from effects of climate ...

Rocky Mountain National Park is home to herds of elk and bighorn sheep, but it also has a population of mountain lions and black bears. Although attacks are very rare, the National Park Service ...