The metro system in Seoul is very clean and the bathrooms are maintained on a regular basis. People are extremely helpful, and my only complaint is that the cards we bought would sometimes not work when trying to get through the gate. People would always help out, but it was a little annoying. There are some stops too, where if you need to change lines, you aren't supposed to swipe your card again, but you are to go to a gate and push the green button. It seemed very odd, but it may have been at stations that didn't originally have connecting lines. So if you accidentally swipe your card at one of these stops to change lines, it might deplete your card. Regardless, it is a great way to travel under most circumstances in Seoul, especially since many taxi drivers don't want to leave their part of town or take you across the river.
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