Kohdensha employees write at their leisure... Travelogue "Subway Situation in Seoul, South Korea

The subway system in Seoul is quite complicated, though not as complicated as in Tokyo.
As of August 2018, there are nine lines running, and they are intricately intertwined underground within Seoul.
In the central area of the city, you can change trains every two stations.

Because of this situation, the Seoul subway runs very deep in some places.
Platforms are located 6 stories underground, and it can take more than 5 minutes to reach the platform from the ground level...

Also, the stations are very spacious. This is because the station is supposed to be used as an evacuation shelter in case of emergency.

There is also a prepaid electronic money card called "T-money" like Suica and Icoca of JR etc.
Even travelers can purchase it at convenience stores in Seoul. I used it myself and found it quite convenient. The first ride is cheaper.

If you are going to Seoul in the future, please give it a try.