As you stroll along Hongje Stream in western Seoul, the gentle sound of flowing water grows with each step, while the breeze carries the scent of grass and spring flowers.

These are signs that you're approaching the city's hidden oasis, where time slows and your thoughts fade simply by watching the water move.

It is the "Hongje Steam Artificial Waterfall" in Seodaemun-gu, where water flows down a 25-meter-high, 60-meter-wide concrete structure built into the cliffs of Mount Ansan.

On a breezy weekday afternoon in April, the human-made waterfall poured water into a pool below, where spot-billed ducks moved in slow, steady circles.

At parasol tables on the sandy ground in front of the waterfall, visitors lost themselves in books, music or the sounds of water, each enjoying a quiet reprieve from hectic city life.

“I like just sitting here and zoning out while watching the waterfall,” said Kim Soo-rin, 25, a university student at Hongik University.

“It’s nice to have a place close to home where I can enjoy nature without having to travel far.”

The traffic noise from the ring roads above the stream was softened by the rush of water, turning the waterfall area into a quiet escape in the heart of the city.

The Hongje Stream Waterfall was constructed as part of the Seoul Metropolitan Government's large-scale restoration project between 2006-2011 to revive the Hongje Stream, which ran dry in the mid-1990s as a result of rapid urban development.

The city revived Hongje Stream by channeling water from beneath the Han River to the stream’s upper section. From there, it flows naturally back to the river.

The artificial waterfall along the stream operates by pumping groundwater through pipes to the peak of the structure, where it is released to flow downward, resembling a natural cascade. The water is then collected below and recirculated, allowing the waterfall to run year-round without relying on external sources.

Each season gives the waterfall a new look. Spring surrounds it with blossoms, softening the concrete, while winter transforms it into a glassy ice sheet.

A two-story cafe overlooking the artificial waterfall has also gained popularity among foreign visitors as an Instagrammable spot.

Repurposed from an old parking lot and warehouse, Cafe Pokpo draws tourists with its outdoor terrace and large glass windows that offer panoramic views of the artificial waterfall.

Since its opening in January 2023, the cafe had attracted 1.4 million visitors as of October 2024, according to the Seoul government.

“I didn’t expect to find a waterfall in the middle of Seoul. It’s pretty incredible," said Marie Schafer, a German traveler in her 30s.

Next to the cafe is a small library called "Pokpo Chaekbang," which houses around 1,500 items, including books, periodicals, and multimedia resources. Visitors can enjoy reading with a full view of the waterfall through large glass windows. The space is open to the public at no cost.

Meanwhile, a short walk across stepping stones toward the artificial waterfall leads to a tree-lined trail, where visitors encounter a large wooden waterwheel that reflects the restoration project’s focus on sustainability and ecological renewal.

As one of Seoul’s emerging urban landmarks, the waterfall often serves as a hub for cultural programs. Earlier in April, Seodaemun-gu hosted various attractions around the waterfall, including food trucks, themed photo booths and a space-out competition.

“This area brings together the vibrancy of the city and the serenity of nature,” the Seodaemun District Office said in a statement.

“By organizing diverse cultural programs here throughout the year, we hope to make it a must-visit spot for both Seoulites and travelers from around the world.”