The country's citizens revere the strange and ruggedly beautiful mountains east of Seoul for their power to soothe the spirit. One South Korean visits the area in autumn, the loveliest time of year, in search of renewal.

I boarded the sunrise train to Gangwon Province just before midnight, imagining that it would be full of lonely people seeking the solace of the mountains and the endless blue sea. Though Gangwon is only a few hours east of Seoul, it is another world. It contains Seoraksan National Park, beloved for its dramatic peaks, deep valleys, and unparalleled autumn foliage. But until recently, Gangwon was one of South Korea’s most treacherous regions. Folktales abound about farmers being devoured by tigers. In the 19th century, bandits were known to take travelers captive. As late as the 1980s, buses made the evening news by tumbling off cliffs.

VIDEO: South Korea's Gangwon Province in the Fall

Today, the roads are much improved, and the area has become more accessible. Visits increased after 2004, when the South Korean workweek was legally changed from six days to five, allowing city dwellers to seek out nature with the same fervor that they devote to company culture. Many South Koreans see wild places like Seoraksan as a remedy for burnout and an antidote to the modernization that has transformed the country over the past five decades. In Seoul, there’s even a trend of camping-themed cafés, complete with tents and picnic tables, simulating the outdoors for those unable to leave town. Koreans commit themselves as intensely to nature as they do to every other aspect of life—eating, drinking, working, loving. The Italians of the East, some call them.

The sunrise train is a decidedly South Korean invention: it leaves Seoul in the dark of night and arrives in the coastal city of Gangneung in time for passengers to sit on a long, golden beach called Jeongdongjin and watch the dawn lighten the East Sea. I’d heard about it from a cousin, who had taken the train as a melancholy student, worried about passing his college entrance exams. After an intense period of work, I was melancholy, too, and like so many South Koreans, I turned to the outdoors for spiritual nourishment.

I was surprised to find my car full of cheerful couples, mothers and daughters, and groups of hikers dressed as if ready for Mount Everest. Few seemed interested in sleep. Teenagers whispered as they watched movies on their cell phones. In the old-fashioned dining car, an elderly couple drank soda. I bought snacks of fried tofu chips and walnut-and-red-bean pastries and listened to a low buzz coming from the miniature karaoke room. When the door opened, five teenage boys spilled out of a space meant for two.

Related: The Only Map You Need to Plan a Perfect Fall Foliage TripLeft: The Ulsanbawi rock formation is one of the most popular destinations in Seoraksan National Park. Right: The park is also home to Sinheungsa Temple, one of South Korea's most important Buddhist sites. Frédéric Lagrange

When we reached Jeongdongjin, salty sea air filled my lungs. I trailed a tidal wave of college students, including one with a football player's build who had wrapped himself in a pink Hello Kitty blanket. These veterans of night trains had come prepared to greet the sun, armed with snacks, fuzzy blankets, and plastic mats. Kids set off fireworks that cut through the mist, then stopped to watch the sea turn from green to blue to coral until the rocks and cliffs began to lose their mysterious mermaid and monster shapes. A soldier appeared suddenly to my left, reminding me that I was not only in one of the most beautiful places in South Korea but also just a short boat ride from North Korea. He propped a leg on a rock and gazed at the sunrise that was now a riot of orange and russet. In the distance, dozens more soldiers marched in the mist.

Later, I found myself behind a truckload of young men in uniform, many probably college students fulfilling their service requirement. I asked Mr. Choi, my driver, about the military presence in the area.

“Soldiers?” he replied. “All we have are soldiers! They come here most mornings as part of their guard duty.”

Amid the surreal beauty, I began to notice camouflaged guard posts, evidence of a land divided by history for more than 60 years. South Korea is best known for its information technology and pop culture, but the coast of Gangwon province is a reminder of the country’s complicated past.

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With a population of about 200,000, Gangneung is the largest coastal city in Gangwon province and a cultural center. Nestled among low mountains, lakes, and shoreline, it recalls an older, slower Korea. But unlike most provincial cities, it is growing, enticing refugees from Seoul with its natural beauty and more humane pace of life. Many traditional buildings remain, including a picturesque Confucian academy and an old city hall complex that has been converted into a library.

At the very heart of Gangneung is Seongyojang, a residence constructed for the Naebeon Lee noble family in the 18th century. Within its peaceful grounds is a blooming lotus pool with a wooden pavilion where aristocrats once came to write poetry, drink, and think. The building is a large hanok, a traditional Korean dwelling. With their signature curving, tiled roofs, these wood-and-clay buildings arranged around a central courtyard are designed to blend the indoors and outdoors. Each of the sliding mulberry-bark doors framed a hill fiery with fall colors.

I approached a more modest structure nearby where a 10th generation descendant of the Lee family lives part of the year. It was off-limits to visitors, but from the cordoned-off entrance I glimpsed a courtyard with dozens of the earthenware jars called onggi that store sauces and kimchi. Laundry hung from a clothesline, and the grounds were silent.

For all of its traditional customs, Gangneung is nonetheless moving into the future. New buildings have risen along its skyline in preparation for the 2018 Winter Olympics ice events, which will take place in nearby Pyeongchang. One is Richard Meier’s Seamarq Hotel, a modern edifice as brilliantly white as a house on a Greek island. The rooms drink in the light, the air, and the azure water. The building so closely hugs the East Sea that from my bed I felt as if I were floating into it.Left: The Seamarq Hotel, in Gangneung, on the East Sea. Right: The hotel’s lobby. Frédéric Lagrange

At first the Seamarq seemed conspicuously modern, but I came to see in its clean, sleek lines and lack of extraneous decoration a relationship with hanok architecture. This became even more apparent when I strolled the grounds and discovered an annex called the Hoanjae suite, a stately modern hanok by Doojin Hwang Architects. Later, in the hotel basement, I found the remains of a fortress dating to the Silla dynasty, which ruled Korea in the first millennium. They had been unearthed during the hotel’s construction.

Chodang Sundubu Village, a cluster of tofu restaurants a five-minute drive from the Seamarq, is a stronghold of one of Gangwon province’s most distinctive delicacies. Many years ago, because salt was not readily available here, cooks seasoned the tofu with well water and seawater, giving it a rich but subtle flavor. Restaurants like Chodang Halmeoni Sundubu (which translates to “Granny Chodang’s Tofu Stew”) still prepare their hearty, humble sundubu in the same way. This being South Korea, where no meal is complete without alcohol, the dish comes with a house-made fermented corn beverage.

"Like so many South Koreans, I turned to the outdoors for spiritual nourishment."

I was eager to head to the mountains and view Korean autumn at its apex. But one cannot visit Gangwon province without trying its seafood. At Jumunjin Fish Market, the largest on South Korea’s eastern coast, I sampled a fresh sashimi rice bowl and potato pancakes. Several locals recommended Unpa, a seaside restaurant near the Seamarq, where the most basic set meal consisted of fresh seaweed soup, crab, mackerel, sole, flounder, and a whole medley of sashimi. Each time I thought the feast had concluded, another dish arrived, as if in a procession of honored guests. The meal suggested a culture, so unlike the one I knew in Seoul, that was given to meandering conversations and leisurely contemplation. I felt I was among people who prefer to experience life rather than race through it.

On my last day on the coast, I walked to the end of the dock and saw the entire shoreline spread before me like a dream. I fantasized about quitting my job and moving into a house by the East Sea where I could live at the languid pace of the locals. But South Korea’s most famous national park beckoned, an hour to the north.

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I reached the entrance to Seoraksan at mid-afternoon, and headed for the Biryong Falls Trail along the base of Seorak Mountain, for which the park is named. A short hike that winds past waterfalls, it was an easy but spectacular introduction to the park. There was a bamboo forest, a stream, and mountains crowned by trees that had burst into an autumnal rainbow of scarlet, burgundy, purple, and saffron. Hikers had built hundreds of tiny pagodas out of rocks, which, somehow, miraculously resist wind and rain. There are surely Buddhists among the homage-makers, but many visitors erect the pagodas simply to honor the mountains, as if they were living spirits.

The only spectacle that competed with the natural beauty was the visitors’ attire. It was easy to understand why so many articles have been written about South Korean hiking fashion. One woman passed me in an oversize magenta beach hat, another in paisley trekking pants. A macho-looking man with wide shoulders and a large stomach wore the sweetest, most whimsical mustard-yellow pants dotted with white clouds, more pajamas than hiking outfit. If any of them had become lost on the mountain, I suspect that the rescue helicopter would have spotted them easily.

Early the next day I set out on the Biseondae Trail, which slopes gently upward to a steep staircase that looks onto jagged peaks and bridges hanging precariously over gorges. Not far from the trailhead I found a girl sitting cross-legged on a boulder, talking on her cell phone. This was Korea, after all. My favorite hiker was the woman who approached a squirrel and asked it tenderly, “Did you collect many acorns today?” Everyone was gentler, kinder, in Seoraksan’s gi, or “energy.” There are six distinct peaks in the Ulsanbawi rock formation. Pine trees cling to their sheer faces. Frédéric Lagrange

Near a collection of large boulders called the Biseondae Rocks, a restaurant serves several hearty dishes typical of the region: seafood and potato pancakes, seasoned-acorn-jelly salad, mixed mountain root vegetables and rice, grilled bellflower root, red-bean ice cream. Early each morning in the dark, I learned, staffers hike Seorak Mountain with supplies packed into old-fashioned wood-frame packs, much like the ones that were used hundreds of years ago. I sat on the patio, basking in the view of a cascading waterfall and sheer granite cliffs. Across from me, two women poured from a large bottle of traditional sweet rice alcohol called dongdongju.

Alcohol is integral to Korean hiking culture. The sensible ones wait till the end before imbibing, avoiding an unpleasant descent. But many are not so sensible. By noon, I had already spotted one hiker sprawled against a rock, his eyes closed and his face the hue of a pink magnolia. Another carried two green bottles of makgeolli, an unrefined rice wine, tucked into the outer pockets of his backpack.

"Many South Koreans see wild places like Seoraksan as a remedy for burnout and an antidote to the modernization that has transformed the country over the past five decades."

At Seoraksan, as at most of South Korea’s 21 national parks, vendors set up just inside the entrance offer feasts to weary hikers. I found spicy buckwheat noodles, grilled pork wrapped in fresh seaweed, potato pancakes, Korean beef barbecue, giant chocolate cream pies. I ate until I was bloated, but I still found room for some imported coffee.

Heung Sub Lim, the owner of a café whose name translates to “The Hanok That Roasts Coffee,” personifes the trend of urban refugees relocating to the area. He quit corporate life in Seoul and surrendered to an enduring attraction to Seoraksan, bringing Jamaican Blue Mountain and Ethiopian mocha Harrar to an area that had previously known only plastic packets of freeze-dried coffee. Even the head monk of nearby Sinheungsa Temple drops in each day. Centuries-old Chinese characters carved into the sheer face of Ulsanbawi. Frédéric Lagrange

When I visited, I found Lim’s slickly dressed employees, who looked more like they belonged in Seoul’s hipster neighborhood of Hongdae than on a mountaintop, serving hikers on a deck overlooking a creek. I spoke with one barista, dressed all in black, who sported a silver hoop earring and a straw hat. “I didn’t have any dreams,” he told me, “until I met coffee.”

Nearby, I found Seoldawon, a teahouse run by Buddhists. In keeping with the Buddhist tradition of offering respite to travelers, the tea is free. While wandering its grounds, I met a curly-haired woman whose accent suggested that she was from Seoul. She declined to give me her name, identifying herself only as a monk’s helper, as if in her new life that was all that mattered. She knew nothing about me, but she took my hand in hers and sat me in a hanok behind the café. “Sometimes I, too, feel empty,” she said. “The mountains have good energy. The places we need to be, the people we need to meet, we will go and meet. That’s what we call fate.”

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The park abounds with paths that can keep even the most industrious visitor busy for weeks. A short trail leads to Geumganggul Cave, where I happened upon a Buddhist monk who prayed for me. A steep, four-hour climb up to the Ulsanbawi rock formation climaxes with panoramic vistas of the mountains. Several day hikes traverse all of Seoraksan. The park also contains major Buddhist sites, most significantly the ornate Sinheungsa Temple, built in the seventh century and subsequently destroyed and rebuilt numerous times. I stopped repeatedly to gaze at the stunning wall paintings.Left: Sinheungsa is the head temple of the 1,200-year-old Jogye order of Korean Buddhism. Right: The 48-foot-tall Great Unification Buddha, near Sinheungsa Temple. Frédéric Lagrange

After several days of superlative views, I thought I’d seen all the highlights. Then I hired a guide named Mr. Byeon, who drove me to the western entrance to visit Naeseorak, the innermost part of the park. A 20-minute shuttle ride took me deep into a valley at the foot of Baekdamsa Temple. The sound of a wooden gong echoed through the early morning fog. Incense smoked around the main altar beside a wooden Buddha sculpture erected in 1748. A line of novice monks wearing wide-brimmed straw hats walked wordlessly into a building, their hands folded together, to begin their day’s studies. The dappled mountains surrounding the temple appeared as if painted by Monet.

At nine in the morning, the only people I met on the trail were those who had come alone to meditate, think, walk, and walk some more. A gray-robed monk with a backpack passed me, his face somber. We made slight bows but exchanged no words.

As the fog lifted, I met more hikers. One pointed out a tree to me and said, “It’s a very old tree, an eight-hundred-year-old tree,” as if making an introduction. This is a country with a brisk market for books that document the famous trees of the peninsula, each with a legend and a history and an age. People talk about trees and stones as if they were animate beings. Observant South Koreans are Buddhist, Protestant, or Catholic, but an echo of Taoist tradition remains in their language and psyche. Industry may have ravaged the country in pursuit of the “South Korean economic miracle,” but the people still venerate the land and revere the mountains as a place of retreat.Left: Fresh octopus at the Sokcho Fish Market. Right: The Biseondae Rocks, in Seoraksan National Park. Frédéric Lagrange

Gangwon province isn’t just an escape, though. It’s a way of life. As Mr. Byeon drove me back to my hotel, he explained the place’s pull: “I did go to Seoul for a few years, then came right back. I mean, you have the mountains and the ocean fifteen minutes from your door. In the summer, I drink and eat fresh sashimi by the river. Here, even a poor man feels rich.”

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The local way to end a long weekend of hiking is to visit a bathhouse, so many trips to Seoraksan conclude at Seorak Waterpia, 10 minutes from the park entrance in the city of Sokcho. I headed for the multilevel outdoor pools. In the daytime, this can be a noisy place, but at dusk it was nearly empty. The few visitors were dressed modestly, in shorts, caps, and long-sleeved cover-ups. They moved from one pool to another, trying out every kind of bath: green tea, jasmine, lemon, barley stone, and the doctor fish pedicure, with tiny garra rufa that nibble the dead skin from your feet.

In a steaming sauna nestled in a landscape of boulders and pine trees, I met a young woman and her mother sipping coffee from paper cups. The daughter told me that her father had recently passed away and they were visiting the area to recuperate. When they slipped back into their conversation, I had my own private moment in a rain spa that was larger than many swimming pools. As I took in the illuminated foliage and waterfall, the months of stress and hurry felt remote, like an experience that had happened to someone else. Maybe it’s impossible to heal oneself completely in a few short days, but I felt warmed, and just a little bit hopeful.

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The Details: What to Do in Gangwon, South Korea

Getting There

Gangwon province, the home of Seoraksan National Park, is accessible via bus and train from Seoul. Buses leave for Gangneung and Sokcho from the Dong Seoul Bus Terminal and the Seoul Express Bus Terminal. Trains depart from Cheongnyangni Station in Seoul. The “sunrise” trains to Gangneung leave before midnight and arrive before dawn.

Hotels

Hanwha Resort Seorak: A 10-minute drive from Seoraksan National Park, this outpost of a respected local hotel chain is good for families. Sokcho; hanwharesort.co.kr; suites from $97.

Kensington Stars Hotel: The British theme may seem slightly kitschy, but the property, only a five-minute walk from Seoraksan National Park, is clean and comfortable. Sokcho; kensington.co.kr; doubles from $124.

Seamarq Hotel: Many of the sleek rooms at this new high-end hotel have unforgettable views of the East Sea. Gangneung; seamarqhotel.com; doubles from $394.

Restaurants & Cafés

Chodang Halmeoni Sundubu: A lovely restaurant in Chodang Sundubu Village that makes an excellent sundubu, a soft-tofu stew seasoned with saltwater from the East Sea. Gangneung; 82-33-652-2058; entrées $6–$9.

Jumunjin Fish Market: Grab sashimi at this 80-year-old market between Gangneung and Sokcho that sells fresh squid, mackerel, pollock, pike, and crab. Jumunjin.

Keopi Bokkneun Hanok: The only café within Seoraksan National Park that serves coffee made from fresh-roasted beans.

Seoldawon: Run by Buddhist volunteers, this teahouse offers free beverages and a place for weary hikers to rest in Seoraksan National Park.

Unpa: A popular seafood restaurant known for its wide range of cooked and raw dishes. Gangneung; 82-33-653-9565; sashimi sets from $45.

Activities

Seongyojang: Once a noble family’s home, this centuries-old complex is one of the best examples of traditional hanok architecture. knsgj.net.

Seoraksan National Park: The park’s official English-language site lists trails, itineraries, facilities, and sites, including Baekdamsa and Sinheungsa temples. english.knps.or.kr.