NORTH CONWAY, N.H. – The trains that once brought the Industrial Revolution steaming into New Hampshire’s White Mountains now usher stressed-out visitors into a leisurely world of scenic rivers, mountains and fall foliage.

“We ask people to kick back, relax and enjoy. You’re not driving anywhere. Just sit back and talk with your family,” said Russ Seybold, general manager of the Conway Scenic Railroad, which runs tourist trains along the Mount Washington Valley and into the mountains.

Scenic railroads are a growing tourist attraction in New England and around the country, offering a nostalgic experience for older passengers who grew up riding trains and a special outing for families with children raised on the toys and tales of “Thomas the Tank Engine.”

For everyone in between, there’s the scenery, lovingly restored old engines and depots, food, and narrations that combine local lore and history.

Tom Gracy, an 8-year-old triplet from Southbury, Conn., who was riding the Hobo Railroad recently with his family, didn’t care about the forest views.

“I just love riding,” he said. “It’s all about the trains.”

His parents say Tom watches “Thomas” videos, plays with toy trains for hours at a time and searches the Internet for subway maps.

When he’s old enough, Tom wants to learn how to drive electric streetcars at the Seashore Trolley Museum in Kennebunkport, Maine, and volunteer there as a junior motorman.

“Whenever we get a chance, we go to train museums and trolley museums,” said his father, Bernie Gracy. “His favorite thing to do in Boston is ride the T.”

Starting in the late 1840s and ’50s, the railroads brought speed and progress to rural outposts in northern New Hampshire, Vermont and Maine, carrying their timber and farm-fresh food to Boston and New York in exchange for manufactured goods.

Other rail lines traversed the mountains from east to west, bringing European goods from seaports such as Portland, Maine, to Montreal, Toronto and Chicago.

Then the trains added passenger service for visitors seeking the wild Eden portrayed in the writings of the Transcendentalists and paintings by the White Mountain school of artists. Around the turn of the 20th century, grand resort hotels sprang up to accommodate a burgeoning summer social scene.

After World War II, the interstate highway system began bringing cars and trucks to every corner of the continent. In New England as elsewhere, the railroads began a slow decline, first cutting back on passenger service, then abandoning many freight lines in the 1970s and ’80s.

But former rail men and train buffs intent on preserving a piece of American history, along with businessmen hoping to breathe new life into the tourist economy, began buying up and restoring old rail lines, engines and passenger cars.

The result was the scenic railroad, a modern creation with an old-fashioned feel.

The Conway Scenic Railroad started in 1974 with a depot, rail yard and seven miles of abandoned track purchased in a bankruptcy. In the early 1990s, the railroad leased another section of abandoned track that runs east to west through Crawford Notch, a line considered an engineering marvel when it was completed in 1875.

The railroad boasts a 1921 steam locomotive, an 1898 Pullman parlor car with stained-glass windows, a 1929 Pullman dining car, and a 1955 Budd “dome coach” with upstairs seats offering a panoramic view.

The Hobo Railroad in Woodstock, started in 1987, likewise tries to re-create the “golden age of railroading” for its passengers, said president Ben Clark.

He recently bought a 1954 Pullman piano and parlor car and the Bangor & Aroostook Railroad’s “president’s car” – complete with luxury staterooms, a formal dining room and a small lounge – to lease for weddings and business functions.

Clark sees his family’s business as a service to future generations.

“This is our life’s work,” he said. “Not only are we helping the tourist economy, we’re preserving these rail corridors for future use.”

New Hampshire’s other tourist railroads include the Winnipesaukee Scenic Railroad in the Lakes Region; the Wilton Scenic Railroad, which opened in the Mount Monadnock region in 2003; the White Mountain Central Railroad at Clark’s Trading Post in Woodstock; and the Mount Washington Cog Railway.

The Cog is unique both in engineering and purpose. It has always served the tourist market, crawling up the Northeast’s highest peak at a heart-stopping 25 percent grade since 1869.

In Vermont, the Green Mountain Railroad offers scenic routes in several parts of the state. Maine has a few independent scenic railways, including the Maine Narrow Gauge Railroad in Portland, with tracks only 2 feet wide.

Except for the Cog Railway, all were rebuilt largely by volunteers and are staffed by former trainmen and rail fans, with talented machinists and mechanics working hard behind the scenes.

“Any old railway like this is an ongoing exercise in futility,” said Albert Coughlin, a model train enthusiast and former bank clerk who works part time for the Conway railroad. “Some parts are no longer available. You have to machine them or beg, borrow or steal them.”

The railroads attract customers with special, all-day trips for rail fans and holiday rides for children, such as the “Polar Express” – a Conway railroad ride based on the popular children’s book.

Some, like the Edaville Railroad in South Carver, Mass., and the Essex Steam Train in Essex, Conn., bring in life-size, working Thomas the Tank Engines for a week or two.

The Cog Railway will run a ski train this winter for the first time.

But the best time to ride the rails in New England is the fall, when every trip is special, thanks to the colorful foliage.

“Fall is a real peak time,” Clark said. “People come from all over the world.”