How does Seoul’s subway system help with traffic congestion?

Seoul’s extensive subway system serves as a vital component of the city's public transportation network, helping to alleviate traffic congestion in the capital. By providing a highly efficient, cost-effective, and convenient alternative to private vehicle use, the Seoul Metro helps manage the significant pressure placed on the city's road infrastructure by its large and expanding population.1

While Seoul has invested in vast road improvements, including numerous bridges across the Han River and circular roads connecting to satellite cities, these facilities have struggled to keep pace with urban growth, often resulting in crowded streets. Consequently, the subway—alongside buses and railways—functions as a primary mode of transit that diverts a substantial volume of commuters away from the city's congested thoroughfares. The system is recognized globally for its high performance, featuring modern amenities such as heated seats in winter and free Wi-Fi on every train.12