What area is korean Inhabit in?

More then 10 million person (More than population's 1/4 korean person, that is the South Korea) is inhabiting in Seoul.
People Is ranging evenly to Seoul.

They Inhabit in distance between 1 hour and 30 minutes.
They use the subway and a bus mainly, and attend office by private car.

Usally, Korean did not stay in downtown.
Because, air is bad and there are no big Market.
Korean majority prefers large scale apartment complex.
Also, many family prefer area in good children's school.
Many wealthy classes live in Songpa-gu, Seocho-gu. Bungdang.