The Korean Peninsula: Division and Geography

The Korean Peninsula extends roughly 1,100 kilometers south from its land border with China and Russia toward the Korea Strait and the Japanese archipelago, flanked by the Yellow Sea to the west and the Sea of Japan (East Sea) to the east. Approximately 70 percent of the peninsula's terrain is mountainous or hilly, most prominently along the Taebaek range, which runs close to the eastern coast of what is now South Korea and produces a markedly asymmetric landscape: steep, narrow coastal plains in the east and broader, gentler lowlands opening toward the Yellow Sea in the west, where most of the peninsula's arable land and largest cities are concentrated.