Seoul Subway Line 2

Seoul Subway Line 2 (Korean: 서울 지하철 2호선), also known as the Circle Line, is a circular line of the Seoul Metropolitan Subway. The line running clockwise is called the "inner circle line" and the counter-clockwise line is called the "outer circle line". This is Seoul's most heavily used line, and consists of the main loop (48.8 km (30.3 mi)), the Seongsu Branch (5.4 km (3.4 mi)) and the Sinjeong Branch (6.0 km (3.7 mi)) for a total line length of 60.2 km (37.4 mi). The Line 2 loop is the third longest subway loop in the world after Moscow Metro Bolshaya Koltsevaya line and Beijing Subway Line 10. In 2019, Line 2 had an annual ridership of 812 million passengers or 2.2 million passengers per day.

Headways on the line vary from 2 minutes 18 seconds on peak periods and 5–6 minutes off-peak periods. The line connects the city centre to Gangnam, Teheran Valley and the COEX/KWTC complex.