When you think of the mountains of Colorado, you think of fresh, clean, crisp air. There is nothing quite like escaping the brown cloud of Denver and the Front Range of Colorado. One of the most popular places to get out of the smog is Rocky Mountain National Park.

Rocky Mountain National Park has gotten so popular, that timed entry has been implemented during the busy summer and fall months to help mitigate congestion and traffic into the national park.

Rocky Mountain National Park always seems to be clean and pristine whenever we make the trip to the national park. However, it's sometimes not always what you can see that can make things dirty. According to USA Today, there are a handful of national parks that rank the worst for pollution.

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The climate report shows that 97 percent of national parks are polluted by unsatisfactory air pollution levels and 98 percent have haze pollution in the United States.

Rocky Mountain National Park is one of the most polluted in the United States


Rocky Mountain National Park is the ninth most polluted national park in the United States when it comes to air pollution. Wildfires in Colorado in recent years have not helped the crisp mountain air of Rocky Mountain National Park and neither has man-made pollution according to the report.

California has five national parks on the list of most polluted. The Sequoia and Kings National Parks are the most polluted national parks in the United States. California also has four out of the five most polluted national parks in the nation.

Top 10 Most Polluted National Parks in the United States

  • 10 - White Sands National Park - New Mexico
  • 9 - Rocky Mountain National Park - Colorado
  • 8 - Guadalupe Mountains National Park - Texas
  • 7 - Indiana Dunes National Park
  • 6 - Death Valley National Park - California
  • 5 - Carlsbad Caverns National Park - New Mexico
  • 4 - Yosemite National Park - California
  • 3 - Mojave National Preserve - California
  • 2 - Joshua Tree National Park - California
  • 1 - Sequoia & Kings Canyon National Parks - California

See more about the pollution and the most polluted national parks in the United States at usatoday.com.

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