Korea.Subway spiderweb

In Seoul, there are 10 subway lines including airport line and I can not explain how many bus lanes there are. They are quite mess. None of these are straight. Even if they are so complicated, they are so convenient.

I have to pay for ride and it costs about 1~1.5 dollars each ride. Also, I can pay by credit card, metro card(daily, ever) or cash. if someone use cash, it was not easy to transfer to bus lane with transfer discount. So, I highly recommend someone who want to travel Korea to use any credit card.
It also use to pay for taxi.