The Seoul Metropolitan Rapid Transit Corporation (SMRT) operates the Seoul Metropolitan Subway system, consisting of 21 subway lines and serving the Seoul Capital Area. With over 10 million passengers daily, it is one of the busiest subway systems in the world and the primary means of public transportation in the Seoul area. The website seoulmetro.co.kr/eng provides information about routes, fares, and real-time service updates for the Seoul subway system.