The Southern Railway (abbreviated SR), headquartered at Chennai, is one of the 17 zones of Indian Railways. It is the earliest of the 17 zones of the Indian Railways created in independent India. It 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. The South Indian Railway was originally created in the British colonial times as Great Southern India Railway Co founded in Britain in 1853 and registered in 1859. Its original headquarters was in Tiruchirappalli (Trichy) and was registered as a company in London only in 1890.