Submitted by Sam Gold, who says:

“Taken last week on Line 2 of the Seoul Metro.  I found these system maps to be close to unusable!”

Transit Maps says: Hard to disagree with Sam here. You’d need some excellent vision or really good glasses to be able to make out all the detail on this map, which crams all of Seoul’s extensive system into an area often used to show just one line or far simpler systems.