South Korea has a predominantly rugged, mountainous terrain that looks like "a sea in a heavy gale." The principal mountain range is the Taebaek-San Maek, which extends in a generally north-south direction parallel to the eastern coast. The South Korea's highest peak, located on the island of Cheju, is Halla-san (1950 m. or 2340 ft.). Plains constitute less than one-fifth the total area and are concentrated in the west along the coast; the coastal plains in the east and south are very narrow. Apart from the eastern coast, South Korea has a highly indented coastline characterized by high tidal ranges. The two longest rivers, the Naktong and Han, rise in the Taebaek-San Maek Mountains, the former flowing south to the Korea Strait, the latter northwest to the Yellow Sea. Other major rivers include the Kum, Yongsan, and Tongjin. Due to Korea's geographic features, the majority of its population is concentrated along inland valleys and coastal plains, which open onto its Western Coast. The capital and largest city of South Korea is Seoul.
Only about twenty percent of the peninsula is suitable for cultivation and mass settlement. Mixed deciduous and coniferous forests cover about two-thirds of the land, but they have been thinned for use as fuel. Principal tree species include pine, maple, elm, poplar, fir, and aspen. Bamboo, laurel, and evergreen oak trees are found in the mild southern coastal areas. Large mammals such as tigers, leopards, bears, and lynx were once common throughout the Korean Peninsula, but they have virtually disappeared due to deforestation and poaching.