The generic term “upstate” covers a lot of ground in New York. In his book “Pages From a Cold Island,” Fredrick Exley dedicates a vehement footnote to what exactly constitutes upstate New York: “To a Manhattanite ‘upstate’ means ‘the uthuh siduh Oddsley’ (‘the other side of Ardsley’),” he writes. “But to true upstaters this notion verges on the laughably blasphemous.” One must be within eyeshot, at least, of the Adirondacks, or preferably of Exley’s hometown in Jefferson County. But the real province of upstate has always been an idiomatic one, connoting above all else: not New York City.

For this simple reason, the Hudson Valley – the main target of his sarcasm – is known regionally as upstate. A popular getaway since the early 19th century, it is home now to a growing number of New Yorkers on permanent vacation, or at least trying to be. Lured by the real estate boom into this rural haven of farmhouses, scenic vistas, and wine trails, many families have made the move beyond Westchester, where they can enjoy the country life while still maintaining professional ties to the city.

The result: a commuter’s upstate. On the other side of Ardsley, and as far north as Poughkeepsie, residents travel regularly to their jobs in Manhattan on the Hudson Line of MetroNorth, one of the largest and oldest commuter carriers in the country. Unlike most commutes, the natural beauty and history of the Hudson River can verge on the recreational, offering funicular views of Storm King Mountain, northern gateway to the Hudson Highlands, and farther south, the rivaling Palisades.

For those eager to learn about what they’re missing, or others curious about some of the sites in the mid-Hudson Valley, MetroNorth provides a convenient package and easy access to exciting day trips that are worth revisiting on your day off.

The identical gray carriages, decaled with block-lettered names (“Rip Van Winkle,” “Washington Irving”), follow the broad silvery length of the river. At one point, the train even travels on the river, or seems to, as it passes over a brief causeway separating Constitution Island from the tidal marshes immediately below Arden Point. Stretching across Sleepy Hollow country and past commemorative sites of the Revolutionary War era, the line makes whistle stops at several landmark villages, with their developed riverfronts, historic main streets, hiking trails, and at least one castle.

The Shortest Route to China

Perhaps the earliest commuter to tour the Hudson River was Henry Hudson himself, an English navigator who first explored the river then known as the Northeast Passage, in 1609. His job: to find the shortest route to China. (A year earlier he had sailed over the top of Russia.) The dangerous twists of the Hudson Highlands ultimately forced him to turn around, and he never reached his destination.

A 15-mile link of the Appalachian Mountains chain, the Hudson Highlands are rocky bluffs that rise impressively out of the river. Generations of sailors feared their treacherous passages, christening them “Devil’s Horse Race,” “Martyr’s Reach,” and “World’s End.” Centuries later, the Highlands would become a strategic zone in the Revolutionary War, referred to as the “Gibraltar of America.”

Mount Beacon, the tallest peak in the Highlands, earned its name from the signal fires ignited by local militia to warn General George Washington of the approaching British. In the 1920s, an incline railway once led visitors up to the 1,500-foot summit with a popular restaurant, casino, and dance hall. Nowadays a two-mile hike, with plenty of rugged ups and downs, is required. Although the fine dining and gambling no longer exist, the view is infinitely more rewarding, and you can still dance if you want. To reach the mountain, exit the Beacon station onto Beekman Street and take the shuttle trolley to Main Street (only $1).

In addition to Highlands State Park, the town of Beacon provides a rich source of attractions, most notably the renowned contemporary art museum Dia: Beacon. Worth the trip for its own sake, Dia: Beacon has received more visitors than the Dia Art Foundation’s other exhibition space in Chelsea. A former box-making factory built by Nabisco, the 240,000-square-foot brick museum is a horizontal totem to minimalism. The permanent collection includes work from Joseph Beuys, Donald Judd, Dan Flavin, and Agnes Martin. The large space accommodates works of ambitious scale, and some installations are specifically created for the site.

Beacon also has a revitalized urban shoreline, currently being transformed into a 23-acre park. Each weekend this fall, a passenger vessel will launch cruises to Bannerman’s Castle, situated between Breakneck Ridge and Storm King Mountain (845-220-2120 or 845-831-1001 information and reservations, $40).

An arresting vision from the railroad, Bannerman’s Castle stands in ruins on Pollepel Island. Along the devastated east wall, three giant letters, “-NAL,” remain visible, cast in cement 4 feet high. Originally, the letters were part of “arsenal,” until a powder house storing gunpowder exploded in 1920. (A large fire in 1969 wreaked further destruction.) An entrepreneur with a growing military surplus business, Francis Bannerman VI had been forced to move his stock of munitions outside Beacon city limits. Raised in Brooklyn by Scottish immigrants, he built his turreted residence in 1900, modeling it on medieval Scottish castles. Early photographs show all the trappings: a grandiose portcullis, gantry crane, and capstan – there were even indications of a future plan to build a moat.

The castle is out of sync with the architecture of the region, a blip from old Europe on the historic map that helped to decide the fate of American independence. In truth, however, Bannerman was quintessentially American: the property, a bold defense of his Second Amendment rights; the design, a realization of the conviction that “each man’s house is his castle,” and the boldly commercial guiding purpose, advertising his company’s name to every passing steamship and train.

If you have time, visit the Bannerman Island Gallery at 150 Main St. in Beacon. Open since April, the gallery exhibits photographs and paintings of the island and its environs by a different regional artist each month.

Half Moon on the Rise

At Breakneck Ridge, a station stop just south of Beacon that has service only on weekends, hikers have another way to see exactly where Henry Hudson and his crew were headed. A sheer escarpment, the Half Moon trail includes some invigorating rock scrambles alongside high drop-offs. For a longer hike, attack Mount Taurus, especially the blue-blazed Cornish Trail, which passes old carriage roads and the remains of a large stone estate.

In the village of Cold Spring, life is good on both sides of the tracks. Main Street has a smorgasbord of antique shops, cafes, and bookstores. The French bistro Le Bouchon (76 Main St., 845-265-7676) is an ideal place for lunch, or stop by Oh Fudge! (5 Stone St., 845-265-4493) for a snack. West of the station is Mayor’s Park, a pavilion and bandstand that affords spectacular views of Storm King Mountain to the north, Highland Falls and West Point to the south, and Crow’s Nest (named for its bowl-shaped peak) straight ahead.

Boscobel Restoration, an early 19th-century mansion turned museum, is a mile south; you can hike it or take the train to Garrison. Its views of the river are dramatically enhanced by the well-groomed estate grounds. From the ideally positioned lookout point, or “belvedere,” the river bends past Sugarloaf Mountain and through the narrow course of Anthony’s Nose (a very aristocratic slope, that). The property – complete with orangery, herb garden, and springhouse – complements the well-preserved Georgian home, built by States Morris Dyckman for his young wife, Elizabeth.

Originally, the mansion was in Montrose, 15 miles south. After the federal government deemed the mansion “excess,” a spirited group of historical preservationists moved the house piece by piece – the foundation, facade, and interior – to its present site. Upon completion, the leader, Benjamin West Frazier, claimed that he would never do it again, even if “the whole of Western culture were at stake.” Take advantage of their hard work by touring the house and picnicking on the grounds.

Near the Garrison stop, you can also try the Glenclyffe Loop, a comfortable trail whose anachronistic name typifies the area. The hike belongs to a circuit of related paths connecting to the Appalachian Trail. Farther downriver is another set of short hikes at Manitou Point Nature Preserve, a choice detour whose entrance is steps from the Manitou station platform. The paths lead through habitats including a hemlock forest and Manitou Marsh.

Design – and Day Trips – for Everyone

A personal favorite of mine is Manitoga, the home of mid-century design guru Russel Wright, who proclaimed that “Good design is for everyone.” An Algonquin name meaning House of the Great Spirit, Manitoga is an alternative to the usual riverside estates. Wright curated the landscape with the goal of integrating design and the surrounding environment, including the scars of severe quarrying. In his “woodland garden,” three paths lead past large moss-complexioned boulders and a small forest of mountain laurel with bonsai contortions. The arrangement of the paths draws attention to different textures beneath your feet, including a log section referred to as the Corduroy path. These paths, too, connect to the larger Osborne Loop and the Appalachian Trail.

If hard vinyl train seats are a tad demoralizing for commuters, the expanded list of available stops offered on weekends will help alleviate the malaise that accompanies boarding the train for work. These sites, and many others dotting the waterfront along the Hudson Line, confirm that the valley is still the “Rhineland of America.”