A few hours by car from both Zürich and Milan, the fertile Alpine tranche known as the Engadine Valley is tucked into a hard-to-reach corner of southeastern Switzerland composed of pristine little villages and anchored by the glamorous ski resort of Saint Moritz toward its southwestern end. Though the idyllic countryside around it is minimally developed and lovingly preserved—it’s also one of only a handful of areas of Switzerland where Rumantsch, a dialect of Latin, is still widely spoken—Saint Moritz is not exactly a secret. English outdoor enthusiasts and German intellectuals like Hermann Hesse and Friedrich Nietzsche flocked there around the turn of the last century, escaping cities that were growing dirtier and denser.

But it was the Niarchos and Agnelli families in the 1960s who would give the ski resort its contemporary social profile. So appealing was its lifestyle of winter sports and high-octane après-ski parties that it inspired a brand of cigarettes. (“Longer, richer, cooler” read the tagline of an ad from 1968 for St. Moritz menthols.) The German playboy Gunter Sachs, once married to Brigitte Bardot, was another key player, ensconced in his penthouse lair in Saint Moritz’s Badrutt’s Palace Hotel, where 10 of Warhol’s “Marilyns” hung in his kitchen. Today, scions have taken over—Rolf Sachs runs his father’s still-hot Dracula Club; chairlift paparazzi stalk John and Lapo Elkann—along with private planeloads of Indian millionaires, Russian oligarchs, and their assorted playmates swathed in ostentatious furs and blinding diamonds.

So far, so Gstaad—but there is a crucial difference between the two moneyed Swiss enclaves. Glitzy Saint Moritz is only one of the Engadine Valley’s abundant offerings. Low-key villages like S-chanf, Celerina, and Zuoz lure a more cerebral crowd, as likely to come for summertime hiking as for high-season dinners at Chesa Veglia in Badrutt’s Palace. Miuccia Prada and Patrizio Bertelli, as well as the Etro family, have homes in the area, and “there are more serious art galleries per square foot than in any other resort region,” says the columnist and dealer Kenny Schachter, who has spent Christmas in Saint Moritz with his family for 25 years. Since Bruno Bischofberger opened his first gallery in Saint Moritz in 1963, this side of the Engadine’s social divide lays greater claim to the sellers and makers of art than to its patrons. Native talents like the 19th-century painter Giovanni Segantini, 20th-century sculptor Alberto Giacometti, and 21st-century polymath Not Vital are more likely to come up in conversation than the latest arm candy of multimillionaire Saint Moritz scenester Arun Nayar.

Susanne Thun has been coming to Engadine since the early 1990s, when she and her husband, the architect and Memphis group designer Matteo Thun, bought two adjoined duplex apartments in Celerina. “So much happens here culturally because people have time to see their friends,” she says. “It’s cold and it gets dark at 4 p.m., so what else are you going to do?” The London gallerist Stephen Friedman and his husband stay at the boutique guesthouse Villa Flor in sleepy S-chanf for a few weeks every summer. “We try to disappear in the summer, but it turns out that here I run into people I really like,” he says. Other habitués include Julian Schnabel, also a frequent guest of Villa Flor; the Brussels gallerist Xavier Hufkens; and Miklos von Bartha, who opened a gallery nearby and who pops in to have coffee every morning with Villa Flor’s owner, Ladina Florineth. To keep things lively, the curator Hans Ulrich Obrist helped launch the Engadin Art Talks in 2010, held at the Hotel Castell, in Zuoz. Just a few minutes’ drive from the elite boarding school Lyceum Alpinum, where many a son and daughter of socially prominent vacationers have been enrolled, the hotel is owned by the artist and collector Ruedi Bechtler. The bar of its pop-casual lobby restaurant was codesigned by the artist Pipilotti Rist, and works by Erwin Wurm, Carsten Höller, Lawrence Weiner, and Peter Fischli and David Weiss are strewn throughout. One of James Turrell’s most contemplative “Skyspace” structures, Piz Uter (2005), can be found just a short stroll away, up a grassy knoll where it frames the peak of Piz Uter across the valley.

The Engadine galleries aren’t hidden, but with the exception of Julian’s son Vito Schnabel’s first permanent home as a dealer, in Bischofberger’s former space on Saint Moritz’s main drag, they don’t compete with the landscape. Passing through the region, you’d be more likely to notice the pine-covered hills, glacier-fed rivers, medieval church towers, and pastel-colored houses that line the cobblestoned village streets.

The facades are festooned with decorative botanical and mythical etchings called sgraffito, and from the outside many of them seem interchangeable. Most are attractive in an unassuming way, built for the farmers, brewers, and confectioners that populated the valley before the hotels opened their doors. Venture inside for a chat with some of the owners, however, and the similarity ends.

Afef Jnifen wears Hermès coat; Jnifen’s own shirt, lederhosen, socks, and boots.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo

With one of Italy’s wealthiest men, the Pirelli CEO Marco Tronchetti Provera, as the family breadwinner, you might expect Afef Jnifen, a former model from Tunisia, to live in a fortress on a hill. In fact, home is a relatively modest compound in the middle of the quiet town of Silvaplana. A pair of medium-size Peter Beard photographs are the only serious art on the living room walls. The high life one town over in Saint Moritz isn’t for her either. “Friends look at me like, ‘What’s wrong with you?’ when I say I’m going home to be with my family, but we love being together,” she says of an extended clan that includes her husband’s adult son and two daughters, their spouses and kids, Jnifen’s son from her second marriage, her son’s long-retired nanny, and a poodle and golden retriever. A judge on Project Runway Middle East, an Azzedine Alaïa bestie, and an active philanthropist for children’s rights and advocate for kids at risk of jihad recruitment, Jnifen exudes a red-carpet style that is glamorous but always dignified. In Engadine, however, she’s all about lederhosen, hiking boots, and Uniqlo flannels. “If you don’t like hiking, there’s nothing else to do! But it’s nice. Nature helps the mind, the skin, everything.”

Dora Ardelli wears Valentino coat; Chanel earrings; Emilio Cavallini tights; Manolo Blahnik shoes.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo

The former director of the Segantini Museum, in Saint Moritz, Dora Lardelli is a native of Bregaglia, one valley over. “There are only about 1,700 of us left,” she says. “We speak a similar dialect to Rumantsch. Sometimes I’ll hear it in the airport—we recognize each other immediately.” Lardelli, who studied archaeology, art history, and Italian linguistics, founded the Oberengadin Cultural Archives on the ground floor of Chesa Planta, a 16th-century manor house in the posh village of Samedan, to organize a seemingly endless supply of centuries-old sgraffito stencils, historic social registers (hello, Nietzsche), and vintage tourism paraphernalia. A better local expert on the valley’s history and culture you will not find, and this one teaches ice skating on the side with her daughter, the former Olympic skater Diana Pedretti. “The Engadine was never really isolated,” she says. “Even in the 19th century, the artists brought an international public.”

Susanne Thun wears Fendi coat; Falke tights; Thun’s own dirndl, hat, jewelry, and shoes.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo

“La regina della Bernina!” shouts Susanne Thun in mock triumph, planting a Prada platform on a cheetah-print ottoman as she poses for her portrait in the apartment she shares with her husband, the architect and designer Matteo Thun, and their sons, Constantin, an artist, and Leopold, a London-based gallerist. Colorful eclectica abounds: Bundles of sweet peas are displayed in Ettore Sottsass ceramic vases, complementing comfortable 1950s green and orange velvet furniture and a plexiglass Hervé Van der Straeten console. If Thun, a former graphic designer and stylist, and the trend-finding force behind Matteo Thun & Partners, is not yet the actual queen of the local mountain range, she has taken a first step by renouncing her Austrian citizenship to become an official daughter of Celerina. “I found this place when I was pregnant with Leopold and we were looking for a hospital near where Matteo could ski,” she recalls. For most of the year, the couple is based in Capri and Milan, where social and professional life is more demanding. In Celerina, the day starts with a walk in the woods—you’ll recognize Thun for her authentic Austrian dirndl and Parson Russell terrier, Toni—and could finish over a dinner with friends, or just reading one of the many hundreds of books in the family library. “I always felt guilty about reading, because with our work, we were running like crazy for 40 years. Now I don’t want to feel guilty.”

Laura Sartori Rimini wears Rochas coat; Manolo Blahnik shoes; Rimini’s own necklace.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo

“It’s not always easy having family as clients,” says Laura Sartori Rimini, who, with partner Roberto Peregalli, heads up the in-demand Milanese interior design firm Studio Peregalli. She’s referring to the three-story compound in Celerina that she gut renovated in 1998 for her in-laws, as well as for her own family of four. The results, at least, are copacetic—and cozy in the extreme. Rimini’s top-floor warren features rough pine paneling and floors; Persian rugs; and a baby Aga in the kitchen, just across from an industrial-looking meat slicer. (Further proof that the Riminis are eaters: enough blue-and-white vintage Blue Willow china to serve an army.) A champion skier in her youth, Rimini was a ­Cortina regular until marrying into a Milanese family with roots in the ­Engadine. (Her father-in-law is Cesare Rimini, a lawyer, writer, and intellectual.) “I really fell in love with the place when I started to work here,” she recalls. “Being a working mom has been tough, but knowing my kids were here, safe during the week, was a great help.”

Ladina Florineth wears Etro coat; Akris pants; Marc Jacobs shoes; Florineth’s own jewelry.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo

If you want luxurious lodgings fit for a dowager queen, try Badrutt’s Palace or the Kulm Hotel, in Saint Moritz. If you want chic simplicity and a chance of running into Callum Innes or Julian Schnabel, book Ladina Florineth’s Villa Flor. Before buying and restoring the 1904 Jugendstil villa in 2009, the soft-spoken mother of one worked variously as a ski instructor in her native Saint Moritz, a makeup artist, an art director for German Elle, and running the Monica De Cardenas gallery, in Zuoz. “It was Bruno Bischofberger who really opened my eyes to art,” Florineth says, noting that her father served as Bischofberger’s mountain guide. Comfortable vintage furniture and a well-stocked honesty bar contribute to the villa’s relaxed salon feeling. Numerous common areas are hung with Florineth’s collection of works by Schnabel, Terry Haggerty, and Luigi Ghirri, and twice a year the place is taken over by Elena Ochoa Foster’s gallery or artists like David Shrigley. “People keep coming back,” Florineth says. “I think I’ve created something unusual here.”

Regula Curti wears Dries Van Noten coat; Hermès shirt and pants; Lock & Co. Hatters hat; Gucci shoes; Curti’s own jewelry.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo

In a featherlight peasant blouse by Vita Kin and a snug leather dirndl vest, with yoga-straight posture and a mellifluous voice that befits her training as a music therapist, Regula Curti has the air of an Alpine Snow White. Serendipity follows her wherever she goes. Like how she met her husband, the media and technology mogul Beat Curti, in 1993: “We both walked to the top of St. Peter’s church tower in Zürich,” she recalls. “And when the bells started ringing, we looked at each other,” and that was it. Or, in 1999, when, with her sister, she found their future vacation home, a 1642 farmhouse in La Punt, across the Inn River from Zuoz. “It had always been owned by women,” she says. Among the historic treasures left behind, Curti discovered sheet music for Protestant hymns, some of which inspired Awakening Beyond, her fourth spiritual-music collaboration with Tina Turner. (The album, which was released last month, is an interfaith production with Buddhist, Muslim, Hindu, and Sephardic Jewish singers.) “The acoustics in the barn are great,” Curti notes of the part of the house that was given a contemporary facelift. (It’s also where animal-themed works by Matthew Barney, Not Vital, Pablo Picasso, and Andy Warhol can be found.) The south-facing half of the house was restored to preservationist standards, including the stunning 1649 pine paneling in Beat’s office.

Karla Otto wears Miu Miu coat; Birkenstock slides; Otto’s own jeans.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo

Running a global PR agency with 320 employees and offices in New York, Paris, Milan, London, Hong Kong, Shanghai, Beijing, and Los Angeles is not a recipe for relaxation. (Karla Otto’s clients include Prada, Marni, Céline, Christian Dior Couture, and Valentino.) “This place feels like a sanctuary,” she says of her three-bedroom apartment in the shadow of the Hotel Castell, in Zuoz. A voracious skier, hiker, and cyclist, Otto started coming to Saint Moritz in the 1980s and acquired her place 12 years ago, when her son started school at the nearby Lyceum Alpinum. The apartment is simple but comfortably furnished: mod plexiglass stools, Scandinavian easy chairs, Hermès throws, and a kitschy plaster Krishna bull in her bedroom—“my own personal Jeff Koons,” she says with a laugh. What Otto, an avowed health nut, appreciates most here is the water. “No need for plastic bottles. Power boats can’t go on the lakes. To have pristine air and water nowadays is so rare and special.”

Nina Flohr wears Gucci coat; Flohr’s own T-shirt.

Photographs by Walter Pfeiffer; Styled by Gianluca Longo; Hair and makeup for all by Giulia Cigarini at Close Up Milano. Photography assistants: Torvioll Jashari, Micha Freutel; Fashion assistant: Sophia Florineth

Nina Flohr is just back from Mozambique, where she is developing an ecoresort, marine-research facility, and community-empowerment initiative. For now, life on the Suvretta mountainside above Saint Moritz, in the luxurious lair she shares with her father, VistaJet founder Thomas Flohr, revolves around puppies. Pluto, a chocolate Labrador, and Gustav, a Korthals Griffon, have been confined to “just a few rooms at a time for now,” she says. Luckily for them, their territory includes the cavernous central living room with sweeping views of Lake Silvaplana. Soon they may be able to venture downstairs to Flohr’s personal suite, with its Gio Ponti desk, curly bison rugs, and works by Abdoulaye Konaté, Marcel Dzama, and Candida Höfer—or, if they are really well behaved, into the indoor pool or private screening room. Flohr left her creative director position at VistaJet to focus on her Africa projects, but she did find the time to work with the designer Ivana Porfiri on the interiors of the house—with an assist from the Milan design gallerist Nina Yashar. “I did the social scene here a lot when I was younger,” says Flohr, who has been coming to Saint Moritz since she was a baby. “It’s all on your doorstop, and you think it’s thrilling. Dracula was the hot spot; we caught some trouble there! But then you get older and start to enjoy other stuff. If tomorrow’s a nice day, I’ll take a rucksack and go hiking for five or six hours with a guide.”

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