High-speed railroad of South Korea connects all the largest cities of the country: Seoul, Busan, Daegu, Gwangju, Daejeon and Incheon. The main railway line is the Gyeongbu Line which connects Seoul with Busan. The next popular route in South Korea is Daejeon - Mokpo, which belongs to Honam Line. There is also a separate line which connects Seoul and Incheon Airport - AREX (Incheon Int'l Airport Line). Here is the list of the most popular railway routes in South Korea:

• Seoul to Busan train;
• Busan to Seoul train; ​
• Seoul to Daegu train;
• Daegu to Seoul train;

• Seoul to Gwangju train;
• Gwangju to Seoul train;
• Busan to Daegu train;
• Daegu to Busan train.

• ​Seoul to Gangneung train;
• Gangneung to Seoul train;
• Seoul to Jeonju train;
• Jeonju to Seoul train;
• Seoul to Daejeon train;
• Daejeon to Seoul train;
• Daejeon to Mokpo train;
• Incheon Airport to Seoul train.

Check out other Korean trains routes.