Largest cities
Seoul 9,586,000 pop., 23,016,000 urban aggl.
Busan 3,349,000 pop., 3,814,000 urban aggl.
Daejeon 1,488,000 pop., 1,557,000 urban aggl.
Highest mountains
Hallasan 1,947 m (6,388 ft)
Jirisan 1,915 m (6,283 ft)
Longest rivers
Nakdong 510 km (317 mi)
Largest lakes
Woopo 8.5 kmē (3.3 sq mi)
Largest islands
Jeju 1,825 kmē (705 sq mi)
Geoje 383 kmē (148 sq mi)
Jindo 363 kmē (140 sq mi)
Ganghwa 302 kmē (117 sq mi)
Namhae 300 kmē (116 sq mi)