Expressways in South Korea

On 2 September 1967, the first expressway of South Korea, nowadays Gyeongin Expressway, was assigned^[1] as Second-class National Highway 95 Seoul–Incheon (2급국도 제95호선 서울인천선) by the presidential decree. The very first section of expressway was opened^[2] on 21 December 1968. At first, expressways were assigned as a part of national highways, but since 31 August 1971, they were assigned as the new separated class: National Expressways.^[3]

Under the new numbering scheme implemented on 25 August 2001,^[4] expressway numbers were assigned based on a grid system, reflecting the layout proposed in the 3rd Comprehensive National Territorial Planning^[5] (Korean: 제3차국토종합개발계획) in 1992. This updated system was influenced by the numbering conventions of the Interstate Highway System in the United States. The details are:

• Trunk routes: These are numbered with two digits. North–south routes are assigned odd numbers, while east–west routes are given even numbers. Primary routes are numbered progressively from south to north or west to east, with the first digit increasing and the last digit ending in either 5 or 0.
• Branch routes: Branch routes off trunk routes have three-digit numbers, with the first two digits corresponding to the main trunk route number.
• Circular routes: Circular routes are numbered in increments of 100, based on the postal code system used from 1988 to 2015.
  • Seoul: 1, Capital Region First Ring Expressway (Expressway 100)
  • Daejeon/Chungcheong: 3, Daejeon Southern Ring Expressway (Expressway 300)
  • Incheon/Gyeonggi: 4, Capital Region Second Ring Expressway (Expressway 400)
  • Gwangju/Jeolla: 5, Gwangju Ring Expressway (Expressway 500)
  • Busan/South Gyeongsang: Busan Ring Expressway (Expressway 600)
  • Daegu/North Gyeongsang: Daegu Ring Expressway (Expressway 700)
• Route numbers ranging from 70 to 99 are reserved for potential use following Korean reunification and are currently unused.
• There are a few exceptions:
  • The Gyeongbu Expressway is an exception to the numbering rules. Due to its critical importance in the network, it retains the route number 1.
  • There are multiple east–west branches on Capital Region First Ring Expressway (Expressway 100), but they are not numbered as the rule of branch routes; instead, they are numbered 110, 120, and 130, respectively.

The current highway shield for expressways is inspired by U.S. highway signage, combining the shape of U.S. Highway shields with the red, white, and blue color scheme of U.S. Interstate shields which are the same colors used in the South Korean flag.

Most of the expressway network is managed by the Korea Expressway Corporation. Since 2000, however, some routes have been constructed and operated by private companies under government approval. These privately operated routes are managed for a limited time before transitioning to public control.

Hi-pass is an electronic toll collection system for the expressways in South Korea.

Some interchanges are designed only for cars with hi-pass.

From Sintanjin interchange, Daejeon to Yangjae interchange, Seoul, a pair of central lanes are dedicated as a bus lane on holidays; technically, it is operated as HOV-6 with cars with 9+ passenger capacity. On weekdays, the restriction is narrowed to Anseong interchange, Anseong to Yangjae interchange.

Since June 1, 1972, all motorcycles except police motorcycles are prohibited from driving on expressways in South Korea, regardless of engine displacement. Before 1972, motorcycles with an engine displacement greater than 250 cc were permitted on expressways.^[7][8]

Since March 15, 1992, all motorcycles except police motorcycles have been banned from certain other roads designated for motor vehicles only.^{[9][10][11][12]} These roads are marked by a circular blue sign with a white silhouette of a car.

• Transport in South Korea
  • Road transport in South Korea
  • Rail transport in South Korea
  • Rapid transit in South Korea
• Highway system in South Korea
  • National highways of South Korea
  • Local highways of South Korea
  • Motorways in North Korea