The South West Frontier line of

Chennai Suburban Railway The Chennai Suburban Railway is a commuter rail system in the city of Chennai, Tamil Nadu, India, operated by the Southern Railways branch of Indian Railways. It is India's second largest suburban rail network in terms of route length and the ...

is the longest line running South-west from Chennai (Madras) City covering a distance of almost 289 km. Suburban services terminate at Arakkonam and MEMU services run till Villupuram Junction.

Chennai Central - Thiruvallur

* This section has 2 dedicated lines for suburban train operations apart from 2 main line for mixed traffic. * EMUs are operated along 3rd and 4th main lines during peak hours. * 5th and 6th rail lines are planned. * 9-car and 12-car EMU are operated in this sector.

Thiruvallur - Arakkonam

* This section also has 2 dedicated lines for suburban train operations apart from 2 main line for mixed traffic. * 9-car, 12-car EMU & MEMU are operated in this sector.

Arakkonam - Katpadi

* 8-car MEMU are operated in this sector.

Katpadi - Vellore Cantonment

* MEMU service operate between

Chennai Beach Chennai Beach (formerly known as Madras Beach) (station code: MSB) is a railway terminus of the Southern Railway network in Parry's Corner, Chennai, India. Built on reclaimed land, the station serves the suburban services of the Chennai Subu ...

and Vellore Cantonment via Katpadi.

Vellore Cantonment -Tiruvannamalai- Villupuram

* This section has been gauge converted and is being electrified along with passenger services are operating since June. Currently five passenger trains ply over this section {{Railways in Southern India Chennai Suburban Railway