Visiting a national park gives you the chance to appreciate some of the country's best natural outdoor spaces and take in the best scenic views.
Many national parks have dedicated zero-waste initiatives, in an effort to keep the spaces as untouched as possible. And there are different kinds of parks - from monuments, to preserves, historic sites, trails, memorials and seashores, so you can take in lots of different environments.
Read more about my trip to San Francisco (my eco-mecca!) in this blog post.