America's National Parks turn 100 today - these gorgeous vintage posters will inspire you to visit

America's National Park Service turns 100 today. If you love stunning mountains, crystal blue waters, stone arches, green forests, or some other aspect of the outdoors, the 413 parks in the system are some of the best places to experience the sense of wonder that nature can provide.

The Park System includes 84 million acres of protected land spread out across the country, in all 50 states - plus DC, Puerto Rico, and US territories around the globe.

This week or weekend is the perfect time to go, as entry to those parks is free through August 28 as part of the birthday celebration.

For inspiration, we've collected a few of our favorite vintage national parks posters, created in the 1930s and early 1940s by people working for the Works Progress Administration.

Check them out: