When originally proposed as a $384 million US dollar public restoration project to teardown transportation infrastructure that had been built over the Cheonggyecheon, a creek flowing west through downtown Seoul, and build a public parkway filled with artwork, bridges, and waterfalls, public criticism was deafening. As soon it opened to the public in 2005, however, the outcry fell silent and the revitalized stream has become a favorite spot amongst Seoulites looking for a slice of serenity in the busy city.
Cheonggyechon is at its most spectacular during the Seoul Lantern Festival, when the creek is lined with fantastical lanterns depicting scenes from South Korean folklore, history, and pop culture.
The lantern festival usually runs during November. If interested, you can check for specifics here.