Unlike it's northern neighbor, South Korea sports an ever growing network of subways, the oldest and largest of which is the MRT in Seoul. A high speed metro known as the GTX is also in the planning stages. Though not part of the Seoul metro system, it will link satellite towns with the Seoul metro and travel as fast as 200 mph.
All of South Korea's existing systems are full metros, though there are elevated metros that are referred to as light rail. European style tram systems are in the planning stages for Yeosu and Ulsan.
Korea's urban railways are divided into two categories: Korea Metro Transit and Korea Urban Transit. So, what's the difference?
According to Skyscraper City ruready1000, "urban transit is operated within one city. Metropolitan tranist is operated
between cities. For example Seoul subway line 2 is urban transit because it's
operated within Seoul only, and Gyeongui line is metropolitan transit because
it's operated between Seoul and Gyeonggi province. But in some cases the
distinctions between them are blurred. For example Ilsan line is classified as
metropolitan transit and operated by Korail, but you can't find the name of this
line on Seoul subway map because it's integrated on Seoul subway line 3 and
operated as one line."
Well, I guess that certainly cleared it up.
According to the Ministry of Land, Transport and Maritime Affairs, the state of urban transit in South Korea is as follows:
Korea Urban Transit
Korea Metropolitan Transit
Korea Urban Transit (Under Construction)
Korea Mass Transit (Under Construction)
We dare you to make sense of this. Go ahead. Let's see you try.
Last but not least, remember that Seoul Line Five is where you're likely to find the best gay head.