(CNN) — There are more than 420 sites in the US National Park System, but only 63 carry the headliner -- capital N, capital P -- "National Park" title.
The most visited of those, Great Smoky Mountains National Park in North Carolina and Tennessee, welcomed a record-setting 14 million recreation visits in 2021. Zion, Yellowstone and the Grand Canyon are other top visitor draws. See full lists of the most popular National Park Service sites here.
But what about the least-visited headliners? Parks that might be especially wild or hard to reach but also uncrowded and largely undiscovered. Let's take a peek at those.
Seven out of the 15 least-visited national parks in 2021 are in Alaska.
It's no big surprise that a good chunk of the least-visited national parks are in the 49th state. Covering close to 665,000 square miles -- much of it wild and often frozen -- getting around the state can be challenging and there's a lot of wilderness to see.
It's safe to say the people who accounted for its 7,362 recreation visits in 2021 were very committed to a wilderness experience. Denali National Park in Alaska, No. 13 among the least-visited parks, saw a whopping 229,521 visits by comparison.
The National Park of American Samoa logged 8,495 recreation visits in 2021.
© Michael Runkel/Danita Delimon/Adobe Stock
Remote islands, a historic fort and more
The second least-visited national park couldn't be more different. National Park of American Samoa is located on a volcanic island arc in the South Pacific, where fruit bats and coral reefs are part of the ecosystem. The park logged just under 8,500 visits in 2021.
Among other non-Alaska entries in the least visited parks list are North Cascades in Washington; Isle Royale in Michigan and Dry Tortugas in Florida.
The latter two are remarkably different island environments. Isle Royale is a wooded island in Lake Superior accessible by ferry or seaplane; Dry Tortugas is 70 miles west of Key West and encompasses open water and a handful of islands, including one that's home to an impressive 19th-century fort.
Nevada, South Carolina, Minnesota and Texas parks also make the 15 least-visited list.
Here's the list for a little trail-less-taken inspiration:
15 least-visited US National Parks in 2021