Southern Railway has completed electrification of its entire broad-gauge network of 5,068 route-km, reaching 100% coverage. The journey began on 11 May 1931, when Madras became the second metropolitan city in India, after Bombay, to introduce electric traction. In 1968, 25 kV alternating current (AC) electrification was commissioned on the Madras Beach–Tambaram section. With this milestone, every broad-gauge route of Southern Railway now runs on electric traction.