In honor of Earth Day, Facebook revealed which of the nation's parks were most frequented in 2013 according to Facebook "check-ins" -- the method employed by many Millennials and other avid social media users to communicate their geographical exploits.
Last year, the following parks were most popular with Facebook users:
1. Grand Canyon
4. Wolf Trap National Park for the Performing Arts
5. Great Smoky Mountains
7. Rocky Mountain
10. Joshua Tree
Of course, NPS keeps its own stats on park visitation. According to the National Park Conservation Association, the following parks were the most visited:
1. Great Smoky Mountains
2. Grand Canyon
6. Rocky Mountain
8. Grand Teton
The two lists are dominated by the natural beauty and geological splendor of the West, attracting both outdoor enthusiasts and, apparently, plenty of social media savvy visitors.