Nature is awesome, right?

Fresh air, picturesque sights, local flora and fauna — it's all pretty great, but we don't give nearly enough credit to the people who keep it that way. Pardon the pun, but nature just doesn't come, uh, naturally.

100 years ago, the U.S. National Park Service was formed and tasked with conserving "America the Beautiful." They've been doing a pretty bang-up job of it ever since.

Photo by Justin Sullivan/Getty Images.

In honor of the agency's 100th anniversary, here's a list of 15 national parks (and a national seashore) you'll want to add to your bucket list.

1. Hawai'i Volcanoes National Park

Warm weather? Check (it's Hawaii, after all). Beaches? Check. THE AWESOMENESS THAT IS TWO ACTIVE VOLCANOES? Check.

Image by jshyun/Flickr.

2. Glacier National Park

Here's one you may want to check out sooner rather than later. Why? Well, the park used to be home to somewhere around 150 glaciers! Now? There are just 25. In the future, there may be none. To paraphrase "Total Recall," get your ass to Montana.

Image by Andrew Kalat/Flickr.

3. Channel Islands National Park

This park is made up of five of the eight Channel Islands off the California coast. Why just five of eight? Well, you know how in high school, there'd be kids who were like, "You can't sit with us!" at lunch and then you'd silently cry in the bathroom and eat your lunch alone in the auditorium? (OK, those last few parts are probably just me...) It's my guess that it's something like that, but I'm probably wrong. But in addition to that, there are beautiful beaches, stunning rock formations, and warm weather.

Image by David Wan/Flickr.

4. Everglades National Park

If you're ever in the mood to see an alligator up close (but hopefully not too close), Everglades National Park is a great place to do it. The swampy Florida ecosystem is unique, and not exactly what you'd find in Nebraska, Iowa, Indiana, or wherever it is you, dear reader, are from.

Image by Diana Robinson/Flickr.

5. Zion National Park

Combining forests with epic rock formations, Zion National Park is a must-see stop should you be traveling through southern Utah.

Image by Zion National Park/Flickr.

6. Cape Cod National Seashore

What makes this eastern Massachusetts seascape so special? Well, it happens to be home to Marconi Station (if you happened to read that as "macaroni station," you are not alone), the site of the first two-way transatlantic radio transmission, and that's just way cool. It's known for its bike trails along with its views of Cape Cod Bay and the Atlantic Ocean.

Image by Jasperdo/Flickr.

7. North Cascades National Park

I'm going to be honest: I put this on the list simply because it's home to the Picket mountain range. What's so interesting about that, you ask? The names of the mountains within: Mount Fury, Mount Challenger, Poltergeist Pinnacle, Mount Terror, Ghost Peak, and Phantom Peak! POLTERGEIST FREAKIN' PINNACLE? That sounds like a badass roller coaster, and now I want to ride.

Image by Rachel Samanyi/Flickr.

8. Denali National Park and Preserve

Denali National Park in Alaska is home to Denali (obviously), the highest mountain in North America. It's also home to a little bit of everything else: forests, glaciers, rock formations, mountains. Plus, it's absolutely gorgeous.

Image by Denali National Park/Flickr.

9. Grand Canyon National Park

It's the Grand freakin' Canyon. NEXT!

Image by Grand Canyon National Park/Flickr.

10. Arches National Park

As its name would suggest, Arches National Park is home to a number of arch-shaped rock formations. The coolest thing, though, is probably Balanced Rock, a formation that includes an upper portion "balancing" on the lower. If you visit, please do not throw rocks at Balanced Rock in hopes of toppling it. Resist the urge!

Image by Arches National Park/Flickr (cropped).

11. Yosemite National Park

If you're a fan of giant sequoia trees, this is the park for you. In addition to some glorious rock formations, there are three groves of ancient sequoia trees in Yosemite. With its high granite cliffs, the park provides some of the most amazing views you'll see anywhere on Earth.

Image by Matt Savener/Upworthy.

12. Yellowstone National Park

This is the O.G. of national parks, going way back to 1872. It's home to some kickass geysers (what up, Old Faithful), hot springs, incredible wildlife, and so much more. You've heard of it ... now get with it and visit!

Image by Yellowstone National Park/Flickr.

13. Acadia National Park

Here's one very special reason to visit Acadia: the sunrise. Cadillac Mountain is located within the Maine park, and it's the first place in the United States where you can see the sun rise each morning. How awesome is that?

Image by TravelUSA/Flickr.

14. Pinnacles National Park

Pinnacles is a newbie to the National Park System (it was added in 2013), but it still brings the heat when it comes to dishing out that national park goodness. Mountains? Got 'em. Trees? Yep. What makes it special, though? Well, it's home to the success story of the almost-extinct but slowly recovering California condors. Victory!

Image by Stanislav Sedov/Flickr.

15. Joshua Tree National Park

This desert national park is found in Southern California. Named after the Joshua tree (no, not the U2 album), it's a pretty cool change of pace from your usual national park experience.

Photo by David McNew/Getty Images.

So happy birthday, National Park Service! You're looking good for a centenarian! Here's to your continued success!

Interested in visiting a nearby national park? Check out the list of free days at parks around the country.