South Dakota (USA) is 63% larger than Korea (North).
Area: 120,538 km2 World Factbook
Population: 24,851,627 (July 2014) World Factbook
North Korea, officially the Democratic People's Republic of Korea, is a country in East Asia, in the northern part of the Korean Peninsula. The name Korea is derived from Goryeo, a dynasty which ruled in the Middle Ages. The capital and largest city is Pyongyang. Wikipedia
South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux Native American tribes. South Dakota is the 17th most extensive, but the 5th least populous and the 5th least densely populated of the 50 United States. Wikipedia