Where in the world?
The flag of South Korea has a white field with a red and blue Taegeuk in the center and four black trigrams in each corner.

Korea (Republic of)

대한민국

Population: 51,780,579

Region: Asia

Subregion: Eastern Asia

Capital: Seoul

Top Level Domain: .kr

Currencies: South Korean won

Border countries

The flag of North Korea has a red field with a blue stripe at the top and bottom, separated by thin white lines, and a white circle with a red star in the center.

Korea (Democratic People's Republic of)

Population: 25,778,815

Region: Asia

Capital: Pyongyang