Cheonggyecheon (청계천) is a 10.84 km-long stream that starts here at Cheonggye Plaza, near Gwanghwamun Gate and passes under a total of 22 bridges before flowing into Han River. It was originally a natural stream, but was covered with asphalt and used as roads after the Korean War, as part of the country’s post-war economic development. Then in 2005, it was once again changed into an ecological stream after a restoration that took three years.
How to get there by subway:
Take Seoul Metro Line 5 and get off at Gwanghwamun Station Exit 5. Cross the street and you can see the giant shell.