6. Katmai National Park and Preserve, Alaska
Katmai is one of the wildest and most remote national parks in the country, and it is famous for one big reason: bears. Every summer, dozens of brown bears gather at Brooks Falls to catch salmon, and you can watch the action from special viewing platforms. It is like stepping into a real-life nature documentary. Visiting the park takes some planning since you can only reach it by floatplane or boat. But once you are there, it is a total wilderness adventure. The Valley of Ten Thousand Smokes, a volcanic landscape created by a massive eruption in 1912, is another incredible sight. Hiking, camping, and photography are popular, and you will find few crowds to share the space with. This park offers a raw, untamed experience that is hard to find anywhere else. And the best part is that there is no entrance fee to enjoy it all.