KTX

The KTX, or Korea Train eXpress, is South Korea's first high-speed rail system.

It serves as a vital transportation network that connects major cities across the nation. Most KTX services begin at Seoul Station and radiate outward to various destinations.

This system was created to solve severe congestion on the Gyeongbu Expressway and the existing Gyeongbu Line. By the late 1970s, these routes were heavily crowded with both people and freight. A high-speed railway provides a way to move passengers quickly without using the same tracks as slower cargo trains.

To achieve high speeds, the KTX relies on specialized infrastructure and power systems. The tracks are electrified, meaning they receive electricity to power the trains. Much of the high-speed line is built on viaducts, which are long, elevated bridges.

Other sections pass through massive tunnels cut through mountains. For example, the Wonhyo Tunnel and the Geomjeung Tunnel are two of the largest structures on the line. The tracks are designed with a standard gauge to ensure stability. The infrastructure is built to handle speeds even higher than the current maximum service speed of 305 km/h.

The development of the KTX happened in several distinct phases. The first phase focused on the segment between the southwestern suburbs of Seoul and Daegu. This phase was completed in 2004 after 12 years of construction. It cost approximately ₩12,737.7 billion to finish this initial section. The second phase involved building the Daegu-to-Busan section and adding more stations. This part of the project included more complex engineering, such as 54 viaducts and 38 tunnels. This phase entered service in November 2010.

History shows that planning for this system began decades ago. In 1972 and 1974, experts from France's SNCF and the Japan Railway Technical Service conducted early studies. Later, a study by KAIST between 1978 and 1981 suggested separating long-distance passenger traffic onto a high-speed line. Construction officially began on June 30, 1992, starting with a test section between Cheonan and Daejeon. The project faced many challenges, including rising costs and environmental disputes. One major dispute involved the Wonhyo Tunnel, which passes under a wetland area. This dispute caused work to stop in 2005 until a supreme court ruling was made in 2006.

South Korea has utilized several different types of rolling stock, which refers to the actual train cars. The original KTX trains were based on the French TGV Réseau technology.

Following successful domestic testing of the HSR-350x, Korea introduced the KTX-Sancheon in 2010. This was a second type of high-speed train operated by Korail. More recently, the country developed the HEMU-430X prototype. This experimental electric multiple unit achieved 430 km/h in 2013. This achievement made South Korea the fourth country in the world to develop a train that runs on conventional rail at speeds above 300 km/h.

Newer generations of trains have continued to arrive in recent years. The KTX-Eum entered service in 2021 to provide updated high-speed travel.

Following this, the KTX-Cheongryong was introduced in 2024.

These different models allow Korail to manage various service needs across the network. The variety of trains shows how the technology has moved from imported designs to domestic innovation.

The KTX is part of a much larger national strategy for movement. In 2010, the government announced a plan to reduce travel times significantly. The goal is to allow 95% of the country to be reached from Seoul in under two hours by 2020. This involves upgrading many conventional lines to support higher speeds. Projects include the Honam High Speed Railway, which branches from the Gyeongbu line toward Mokpo. By connecting more regions through high-speed rail, the KTX helps integrate the entire nation's economy and social life.