Seoullo, or Seoul Street, is set to open May 20 in South Korea’s capital. The mile-long stretch of highway overpass that had been destined for demolition has cafes, trampolines, and 250 kinds of plants and trees. (Seoul Metropolitan Government)

The South Korean capital is not famed for its aesthetics. Built up quickly during the country’s astonishingly fast industrialization, it’s often been derided with the saying: There’s no soul in Seoul. 

But the city has a new initiative to change that: Seoullo, or Seoul Street, an elevated urban walkway similar to New York’s famed High Line

Built on a mile-long stretch of highway overpass that had been destined for demolition, Seoullo 7017 is to open on Saturday. (It’s named for the year the overpass was built — 1970 — and the year the walkway opens.) 

It will link the Namdaemun market, a ramshackle tourist hot spot that has been in decline for a decade, with a neglected neighborhood on the western side of the railroad tracks that run into Seoul Station. The area around the station is not exactly salubrious either, with its underpasses and sidewalks having become a magnet for homeless people. 

“This will not only restore the overpass, but become a catalyst for the revival and regeneration of neighboring regions through the high number of visitors,” Seoul Mayor Park Won-soon said during a recent visit to the site.  

After it emerged from the Korean War, Seoul was rebuilt almost in the blink of an eye as South Korea began its transformation into an economic powerhouse. Starting in the 1960s, city planners ordered the construction of dozens of elevated highways to keep traffic flowing through the capital. 

Fast forward a few decades, and these hulking overpasses became not only a blight on the landscape, but also a safety risk, as heavy use literally shook their foundations. In 1994, one bridge across the Han River, which bisects Seoul, collapsed, killing 32 people. 

In recent years, the overpasses have gradually been coming down.  

One in the center of the city was torn down to make way for Cheonggye Stream, a seven-mile-long artificial river that opened in 2005. With paths and bridges, it has transformed its environs, attracting locals and tourists at all times of the day and night. The sunken parts in the city center are also several degrees cooler than street level, providing welcome respite in the humid summer. 

The highway over the tracks into Seoul Station was found to have serious safety problems in 2006 and had also been slated for demolition. But it got a reprieve when city planners realized it could be turned into a walkway instead, as the High Line was. 

“Seoul lacks green space,” said Kwon Wan-taek, the city official in charge of the project, as he led reporters over the walkway, where workers were planting in pots and installing lights. “Pedestrians need green areas, but it costs a lot to find new land. It’s much more efficient to turn old space into green space instead of tearing it down.”   

Almost half of Seoullo’s $53 million construction cost has been spent on strengthening the overpass and ensuring that it is safe for large numbers of pedestrians. It is designed to bear the weight of 50,000 people, 10 times the number that will actually be allowed onto the walkway at any one time.

The project is part of a wider urban regeneration effort that has seen the creation of pedestrian-only streets and redesigned sidewalks to make the city more walker-friendly. 

Seoul is home to some 10 million people; the greater metropolitan area, incorporating bedroom communities, has a population of 25 million.  

The walkway will have planters with 250 kinds of trees and plants, all in alphabetical order and with QR codes so visitors can learn about the flora. It will be illuminated with LED lights that will make the whole structure glow blue at night.  

The project was designed by the Dutch architecture group MVRDV. 

Unlike the High Line, built on an old rail line on Manhattan’s Lower West Side, the walkway will connect with buildings — there are already bridges into an office tower and a hotel — and will have cafes and performance areas. There are even trampolines for kids — with fences to make sure they don’t bounce over the edge.  

John Hong, a professor of architecture at Seoul National University, said the overall vision for the project was awesome.

“Seoul is peeling back these previous layers of progress,” he said. “But instead of just tearing it down, the city is saying, ‘Why don’t we keep it and make it into history?’ ” 

The west side of the tracks has been neglected over the years, but the walkway will make the area more accessible. Developers hope it will enable people to discover forgotten parts of Seoul, such as an old Catholic church and a laurel known as “Hitler’s tree,” grown from the sapling the German dictator gave to Korean marathon runner Sohn Kee-chung for winning gold at the 1936 Berlin Olympics.

The project hasn’t been without controversy. Residents and vendors at the market end of the walkway are up in arms that there has been no plan for parking or easing traffic in the already-congested area. And expectations of development at the other end of the walkway have led to rampant real estate speculation. 

But Hong said the overall project should create a sense of community in a part of the city that has been severed by railroad tracks for decades. 

“It’s not just about this little piece of highway,” he said. “It’s about the way it connects all these neighborhoods together.”