Southern Railway (SR) is one of the eighteen zones of Indian Railways. It is headquartered at Chennai and operates across the states of Tamil Nadu, Kerala, Andhra Pradesh and the union territory of Puducherry. The origin of the Southern Railway can be traced back to the Madras Railway formed in 1845. Southern Railway was created on 14 April 1951 by merging three state railways, namely, the Madras and Southern Mahratta Railway, the South Indian Railway Company, and the Mysore State Railway and became the first railway zone created in newly formed India. Southern Railway maintains about 5,081 km (3,157 mi) of railway lines and operates 727 railway stations. It has the distinction of operating the first railway line in India, which opened for traffic from Redhills to Chindadripettai in Madras on 12 September 1836.
