The best place to experience South Korea's k-hiking? Seoul's urban mountains

It’s Saturday morning in Seoul. K-pop blares out from the boutiques and coffeeshops of Hongdae. Shoppers browse the stalls of Namdaemun Market, picking up ingredients for lunch: softshell crabs, lotus roots, plastic-wrapped baskets of Korean pears, cabbages for kimchi-making. Teenagers throng the neon-lit stores of Myeongdong, while their grandparents shop for traditional cure-alls among the old wooden-fronted shops of Jegidong: deer antler for bone health, wormwood for digestion, ginseng for memory.

High above the city, however, there’s another Seoul that feels far removed from the smog and bustle. I’m standing on the slopes of Naksan, one of the wooded peaks that surround the old city, where a group of hikers are getting ready for a day in the mountains. Bantering as they prep their gear, they check daysacks, lace up trail shoes, zip up Gore-Tex jackets, fill up hydration packs and don polarised shades. One of them produces a hat that’s topped, jauntily, by a rainbow-striped parasol. They extend their carbon fibre hiking poles and set off up the mountain at a brisk clip. They’re clearly all seasoned hikers, trail-fit and undaunted by the trek ahead. But there’s something unusual about this group. Not one of them is a day under 70. In fact, the oldest is a sprightly 83.

Hiking — or K-hiking (Korean-hiking, like K-pop), as it’s now become known — is South Korea’s most popular sport. Every weekend, thousands of people pull on their boots and head for the country’s mountains and national parks, and Seoul is no exception. Miles of trails wind around the metropolis, either heading up into the rugged mountains of Bukhansan — the wild national park just a few miles from the city centre — or climbing the summits that ring the city like the points of a crown: Namsan, Naksan, Bugaksan and Inwangsan.

This morning, my fellow hikers and I are following one of Seoul’s most popular routes: the signposted trail along the city’s medieval city walls. Zigzagging over the hilltops for 12 miles, this great battlement is Seoul’s answer to China’s Great Wall, but most visitors aren’t even aware it exists. For much of the route, it’s concealed by woodland. Construction of the city walls began in 1395. Originally it consisted of earthen embankments punctuated by eight gates, one at each compass point. Later, the wall was fortified with granite blocks, spiked by crenellations and watchtowers. For the past 600 years, it has protected the city from outsiders and invaders, and while not all the wall has survived the centuries intact, much of it has been restored. South Korea’s military still guards some sections, particularly around the presidential palace, where barbed wire loops over the fences, radio towers point skywards and security cameras gaze outwards like insectoid eyes.

Today, I’m trekking the northern section of the wall to the summit of Ingwansan, the dome-shaped granite peak that looms on the northwest side of the old city. It’s warm work, but a soft breeze provides some respite from the morning heat. Copses of swaying willow, maple and cherry trees offer patches of shade, and the scent of juniper and mountain pine drifts on the wind. Thoughtfully, air blowers are stationed at many of the trailheads to help people cool off on their climb.

(South Korea has never been more popular—here's why you should visit.)

As the trail follows the wall’s winding course, I pass three of the original city gates: first the northeastern post of Hyehwamun, then northern Sukjeongmun and finally the northwestern gate of Changuimun, which sits between the neighbouring peaks of Bugaksan and Inwangsan. Once, these great fortified gates allowed people to enter and exit the old city and were heavily guarded. Later, they fell into disrepair. They’ve since been gradually restored in a project that began in the 1970s.

At Changuimun, I meet up with Kim Seong-yeop and his friends, a group of hikers in their late twenties. Resting against the wooden gates, they hand around energy gels and isotonic drinks, consulting their watches for readouts on heart rate, distance travelled and calories burned. “We hike every weekend if we can,” Kim Seong-yeop says, in between munching on a rice ball. “There are so many trails around the city, you never get bored.

And when we want more of a challenge, we go into Bukhansan for rock-climbing or scrambling. It beats sitting in an office for the rest of the week.” He checks the next section of the route on his phone — only old folk use paper maps these days, he says, laughing — then sets off up the mountain with his companions.

At 338m, Inwangsan isn’t all that high — but at times, it’s punishingly steep. To help hikers negotiate the gradient, steel staircases and stone steps are etched into the mountainside. As I climb, the woodland gradually thins out into scrub, then vanishes altogether, replaced by smooth flanks of rock and slabs of slippery granite. At the top, a sweeping panorama unfolds over downtown Seoul. Across the city, the steel needle of N Seoul Tower, topped by its blinking light and candy-striped pinnacle, juts from the top of Namsan mountain. Beneath it, among Seoul’s urban sprawl, I can just make out the hazy outline of the Han River, bisecting the city neatly into north and south.

Later that afternoon, I head down into the city to explore another waterway, which — though much smaller than the Han ­— is just as important in its own way. Cheonggyecheon Stream is one of Seoul’s original rivers, a lifeline for the city since its settlement. But in 1969, an inexplicable decision was made to cover it with a 10-lane freeway. It became a hated eyesore, smog-smothered and traffic-choked, infamous for tailbacks, accidents and pollution. In 2003, Seoul’s city mayor, Lee Myung-bak, took the bold decision to remove it. The highway was dismantled, the river was cleaned up and nature rapidly returned.

It’s now a green oasis in the centre of the metropolis. Around 60,000 people use it every day: joggers, dog-walkers, office workers, pram-pushing parents. Avenues of willows line its banks. Cranes and egrets strut in the shallows. Sometimes, fish flash downstream. But Cheonggyecheon is more than a beauty spot: studies have shown it has helped reduce Seoul’s urban heat island, lowering summer temperatures by as much as 4C. And in spring, when snowmelt from the mountains floods into the city, Cheonggyecheon acts as an emergency culvert. Some years, the water level rises by two metres or more.

“Many people are surprised how close Seoul is to the mountains,” says Lim Do-yeon, another keen hiker who I meet along the ‘stream’, as it’s often known in the city. Dressed in trail shoes and trendy running gear, her short hair concealed under a cap, she loves to walk as much as she can: she moved to Seoul for college, and takes every opportunity she can to get out into nature.

“I grew up in a little mountain village a long way from Seoul, so I’m grateful for the scenery and for the peace and quiet. It’s an escape from the noise and stress of everyday life. And I love the sense of camaraderie. People always say hello as they pass here, and sometimes, if you’re lucky, they might even invite you to share a cup of makgeolli at the top,” she says, referring to the boozy, fermented rice wine beloved by many Koreans. “And that’s something you would definitely only get hiking here.”

5 more ways to see Seoul

Shop for souvenirs at a flea market

Seoul is spoiled when it comes to markets — there’s Gwangjang for street food, Namdaemun for local atmosphere or Myeongdong for night-time shopping — but for souvenirs, the sprawling Seoul Folk Flea Market near Sinseoldong station is hard to top. Come for vintage vinyl, handpainted signs or antique handicrafts.

Wander Bukchon Hanok Village

In a city of skyscrapers, this low-rise neighbourhood feels like stepping back into another age. It’s the best place in Seoul to see traditional hanok houses, many of which have been turned into cafes, art galleries, B&Bs and boutiques.

Hang out in Hongdae

A pulsing, neon-lit neighbourhood of crisscrossing lanes and people-packed boulevards, located near Hongik University in the west of the city — Hongdae is the heart of happening Seoul. Visit for street art, cold-brewed coffee, cutting-edge fashion and K-pop karaoke.

Visit the National Folk Museum

Delve into shamanism, folk songs, Korean legends and the terrors of Cheuksin the toilet ghost at this museum. You’ll need a couple of hours to explore its collection of costumes, furniture, musical instruments, artworks and architecture.

Take in the view from N Seoul Tower

Spiking 236 metres from the top of Namsan, Seoul’s guardian mountain, this 1970s tower has an observation deck that offers the ultimate pan-Seoul panorama. Come at sunset for views over the twinkling lights of the metropolis.