The Korean Peninsula extends southward from the northeastern section of the vast Asian continent, spanning 1,000 kilometers north to south. It shares most of its northern border with China and touches Russia. At the end of World War II in 1945, the Peninsula has been divided into two parts, and three years later, the Republic of Korea was established in the south and the Democratic People's Republic of Korea in the north.

The Korean Peninsula is 222,196 square kilometers, almost the same site as the U.K. or Romania. The administrative area of the Republic of Korea is 99,434 square kilometers, slightly larger than Hungary or Portugal and a little smaller than Iceland. Korea has a varied terrain, though about 70 percent of the territory is mountainous. The spectacular Taebaek mountains run the full length of the east coast, where the lashing tides of the East Sea, have carved out sheer cliffs and rocky islets. The western and southern slopes are very gentle, forming plains and many offshore islands honeycombed with inlets. The irregular shoreline is dotted with over 3,000 islands.

The Peninsula has many scenic mountains and rivers, so Koreans often call it the "land decorated with golden embroidery." The highest peak is Mt. Baektusan, or the Ever White Mountain, which stands 2,744 meters high on the northern borderline facing Manchuria. This extinct volcano, with a crater named Cheonji, or Heavenly Lake, on its top, is shrouded with a mythical aura as the site of the first kingdom in Korean history, dating back some 5,000 years. The mountain is also noted as a rich depository of wildlife. Considering the size of its territory, Korea has a relatively large number of rivers and streams which have played important roles in developing industries and lifestyles. Both of the two longest rivers, the Amnokgang River (Yalu, 790km) and the Dumangang River (Dumen, 521km), originate at Mt. Baektusan and flow to the west and the east, respectively, to form the Peninsula's northern border.

In South Korea, the Naktonggang River (525km) and the Hangang River (514km) are the two major rivers responsible for irrigation and industrial water supply. The Han-gang River flows through Seoul, the capital of the Republic and serves as a lifeline for the large population in the central region, including Seoul's 10 million residents. The river also played a significant part in the development of Korea's ancient civilization. The Yellow Sea, lying between Korea and the People's Republic of China, and the ocean south of the Peninsula form a continental shelf with the shallow sea floor providing valuable resources for the fishing industry. Surrounding the Peninsula on three sides, the sea has played a remarkable role in Korean life since ancient times, contributing to the early development of shipbuilding and navigation skills. In recent years, the seabed off the southwestern coast has been explored for petroleum deposits.