Southern railways

Southern Railway, in its instant form, came into existence on 14th April 1951 by the unification of the three state railways namely Madras and Southern Mahratta Railway, the South Indian Railway, and the Mysore state railway.

Southern Railway’s present network broadens across a large area of India’s Southern Peninsula, covering up the states of Tamilnadu, Kerala, Pondicherry, and a small portion of Andhra Pradesh. Processing these naturally abundant and culturally rich southern states, the SR extends from Mangalore on the west coast and Kanniyakumari in the south to Renigunta in the North West and Gudur in the North East.
Headquartered at Chennai, the Southern Railway consists of the following six divisions.
1. Chennai
2. Tiruchirapalli
3. Madurai
4. Palghat
5. Trivandrum
6. Salem

http://www.sr.indianrailways.gov.in/