In the middle of Seoul's concrete jungle flows a stream—11 kilometers of water, greenery, and tranquility crossing the city's business center. Cheonggyecheon Stream is one of the world's most impressive urban renewal examples: a place that was once a dirty river, then an overpass, now the favorite walking spot of millions of Seoulites.

History: From River to Overpass and Back

Cheonggyecheon isn't an artificial canal but a real river that flowed here for centuries. During the Joseon era (1392-1910), this was the capital's main waterway: cargo was floated, laundry was washed on banks, royal pa...