In a fast-changing world, the permanence of our favorite hiking trails is comforting. Apart from the occasional closure, reroute, or bump in crowds, most of us could go back and hike the same miles again and again, and enjoy the enduring views. But decades from now, will that still be true?

　　With the help of the National Park Service’s historical photo archive, we’ve collected nine photos of popular American trails taken between 1930 and 1996. You’ve probably heard of most, if not all, of these well-visited spots. See if you can recognize what they looked like back in the day; you’ll want to pay attention to geological formations, the skyline, and the few clues we’ve offered you. Scroll to the end for the answers.

　　1.

　　This trail is a household name in the US and around the world, with more than 10,000 people having finished it. But it wasn’t always that way, especially in the decades before the hike enjoyed the amenities it does now.

　　2.

　　This burly hike is the most straightforward way up one of the National Parks’ most iconic peaks, but that doesn’t mean it’s easy. Hikers who brave it still need to keep an eye on the weather and watch out for snow that could send them tumbling down a steep drop.

　　3.

　　Want to hike this popular trek in the desert southwest? Hope you’re ready to get wet. Whether you do it as a dayhike or an overnight, you’ll spend miles wading up a river and marveling at the geological scenery.

　　4.

　　This might as well be America’s national hike. In the 100 years since construction began on it, it’s drawn millions of day-, section-, and thru-hikers, and has become a byword for finding yourself.

　　5.

　　As you might guess from the retro-casual apparel, this hike is more of a stroll than a true wilderness experience. But the wildlife—which is bigger and toothier than most national parks’—is enough to capture your attention.

　　6.

　　It’s still possible to traverse this iconic, steep trail by mule. But today most visitors who brave it carry their own gear, with a few hardy souls attempting to run it.

　　7.

　　Look hard at this black-and-white snapshot, and it may begin to look familiar: Some of the most famous scenery in one of America’s most beloved national parks is visible in this mid-trail picture.

　　8.

　　You’ll need a permit nowadays to hike this famous high-country trail, which crosses through three different national parks over its span.

　　9.

　　All right, so it’s not technically a hike. But this ultra-classic (and ultra-ultra-popular) lookout is accessible by a number of different trails. (Start early, and carpool if you can.)

　　Answers

　　Pacific Crest Trail. In this undated archival photo, hiker Dick Kerns poses next to Tunnel Falls on an Oregon section of the trail which doubles as a beloved local dayhike, the Eagle Creek Trail. Keyhole Route, Longs Peak, Rocky Mountain National Park. The rock formation that gave one of RMNP’s premier hikes its name is visible in this undated archival photo. The Narrows, Zion National Park. A group of hikers enter the Narrows via Deep Creek in this 1955 snapshot. Appalachian Trail. It’s a little hard to tell where on the AT photographer Richard Frear snapped this undated photo, but it’s a safe bet that hikers are still enjoying that scenery today. Anhinga Trail, Everglades National Park. This 0.8-mile boardwalk, pictured in 1971, traverses a freshwater sawgrass marsh. A variety of birds—as well as alligators—are common sights there. Bright Angel Trail, Grand Canyon National Park. Bright Angel was considerably quieter in 1930, when this photo was snapped. West Rim Trail, Zion National Park. Visible from left to right, eagle-eyed viewers will spot the Great White Throne, Angels Landing, Gothic Arch, and East Temple, all snapped in 1932. John Muir Trail. The alpine lake and peaks of Evolution Basin tower over the trail, which runs concurrently with the PCT at the spot, in this 1976 photo from Kings Canyon. Cadillac Mountain, Acadia National Park. Back in 1996 when this photo was snapped, anyone could drive to the top; starting in 2019, however, the national park began requiring reservations. Yet another reason to hoof it. Lead Image: A snowy scene high on the Pacific Crest Trail