Seoul is known for skyscrapers and smog, not nature and wildlife. However, just outside of Gangnam proper lies Yangjae stream.
A student told me that when he was growing up, rebellious kids would hide under the overpass and smoke cigarettes. Now mallard ducks paddle through clear water, and remarkably large fish lie just below the surface, looking for flies.
It’s a beautiful reminder of what Seoul used to look like, long before the days of industrialization.