Transportation in South Korea is provided by extensive networks of railways, highways, bus routes, ferry services, and air routes that criss-cross the country. All cities have cross-country bus and intracity bus systems.

Korail provides frequent train service to all major South Korean cities. Two rail lines to North Korea are now being reconnected. The Korean high-speed railway system is known as KTX (Korea Train Express). The principal railway line is the Gyeongbu Line, which connects the capital and largest city (Seoul) with the country's second largest city and largest seaport (Busan); the second is Honam Line, which branches off of the Gyeongbu Line at Daejeon, and ends at Gwangju or Mokpo.

Highways in South Korea are classified into freeways (expressways/motorways), national highways, and various classifications below the national level. Korea Highway Corporation operates the toll highways and service amenities en route. South Korea has about 3,000km national highways. Most tourist and freight transportation use highways.

Railways :
total: 2,600 km
standard gauge: 178 km 1.435-m gauge
narrow gauge: 2,169 km 1.000-m gauge
dual gauge: 253 km three-rail track combining 1.435-m and 1.000-m gauges (2004)

Highways :
total: 93,300 km
paved: 23,418 km
unpaved: 69,882 km (1999 est.)

Waterways :
17,702 km (5,000 km navigable by vessels up to 1.8 m draft) (2004)

Pipelines :
condensate/gas 432 km; gas 210 km; oil 3 km; refined products 206 km (2004)

Ports and harbours :
Cam Ranh, Da Nang, Hai Phong, Ho Chi Minh City, Ha Long, Quy Nhon, Nha Trang, Vinh, Vung Tau

Merchant marine :
total: 194 ships (1,000 GRT or over) 1,170,621 GRT/1,798,376 DWT
by type: bulk carrier 18, cargo 142, chemical tanker 3, container 2, liquefied gas 4, petroleum tanker 22, refrigerated cargo 2, roll on/roll off 1
registered in other countries: 11 (2005)

Airports :
24 (2004 est.)

Airports - with paved runways :
total: 21
over 3,047 m: 6
2,438 to 3,047 m: 5
1,524 to 2,437 m: 9
914 to 1,523 m: 1 (2004 est.)

Airports - with unpaved runways :
total: 3
1,524 to 2,437 m: 1
914 to 1,523 m: 1
under 914 m: 1 (2004 est.)