The northbound Metro-North train stopped on a recent Saturday at the small platform on the west side of Route 22 in Pawling, just mere yards from the Great Swamp.

Erin Krueger, Aaron Pagoda and Camilla Bettig, 15-year-olds from Brooklyn Technical High School, hopped out followed by Jeremy Smith and Santino Romero and Smith’s golden doodles, Gatsby and Daisy Buchanan.

The kids were going to spend a few hours hiking as a fun start to their mid-winter break.

“We’re just going to wing it,” Bettig explained.

The next train brought Warren Lawless, 32, of New Jersey, Tiffany Johansen, 27, of Queens, Chelsea Miles, 30, of Queens, and Stephanie Lum, 26, and David Lisuk, 29, of Manhattan.

The Lawless-Johansen-Miles friends, originally all from Oregon, looked at their surroundings and the roughly four-inch snow cover that persisted despite abnormally warm temperatures, then looked at their sneaker-clad feet.

“We didn’t think about that,” Lawless said, smiling. “We’re used to concrete streets,” Miles added.

Wearing hiking shoes, Lum and Lisuk were going to backpack to a nearby shelter, sleep the night, then return to the city the next day.

“We thought we’d see if we like it,” Lum said of winter backpacking.

Smith and Romero, both 32 and former classmates at Chicago’s Whitney Young High School, planned to hike 10 miles north with Smith’s dogs, camp overnight, then hike back as part of Romero’s visit to New York.

“I spend enough time in the city. I like to get out whenever I can,” Smith said.

The train stop is the only one directly on the 2,200-mile Appalachian Trail and the only stop specifically built to serve the trail, according to Tenny Webster, Appalachian Trail Conservation information specialist in Harpers Ferry, West Virginia.

“People call. The ones from New York I always direct to Metro-North if they don’t have access to a car,” Webster said. “I wish there were more points along the trail that had access like this.”

The AT is one of two Metro-North stops designed specifically for hikers. (Manitou in Philipstown serves some homes and Manitou Point Preserve.)

The other hiker-designed stop is Breakneck Ridge off Route 9D, just north of the Village of Cold Spring.

These aren’t traditional rail stops. Platforms are small, there are no actual stations and service is limited.

Trains stop at both only weekends and holidays. The AT trains leave Grand Central at 7:50 and 9:51 a.m. and arrive just under two hours later, with 2:47 and 4:47 p.m. departures.

Stancy DuHamel, a Wingdale resident who co-chairs the Harlem Valley Appalachian Trail Community, which promotes and protects the trail, said while older people hike the area, she sees mostly people 17-through-20s arrive by train.

Metro-North keeps no records of trail-stop usage. But DuHamel guessed about 30 a day arrive from late spring into fall.

“It’s so great. It’s so easy from the city,” she said.

Local merchants also seem to have embraced it with hiker-targeted signs for things like ice cream and camping.

Breakneck, with views of the Hudson, is wildly popular.