By road
Chennai is one point on the Golden Quadrilateral project, the construction of limited access divided highways that link circumnavigate the heart of India.
Chennai has one of Asia's largest bus stations, CMBT. Seven different state owned corporations fly buses to and from various destinations within South India. There are hourly buses for places like Tirupati, Pondicherry, Coimbatore. You will get the option of A/C or Non-A/C coaches for cities like Bangalore, Trivandrum, Hyderabad.
Several private players also operate buses between most southern destinations. During the weekends most buses are fully occupied and it's better to reserve a ticket in advance. All buses terminate near Koyambedu but there are different stands for state ownedCMBT, and private buses Omni bus terminus. Both these terminuses are near each other, and it is better to tell your exact destination to the taxi/autorickshaw driver. Buses usually drop passengers at various points in the city before reaching the terminus. So feel free to ask the driver or fellow passengers the closest drop-off point to your destination.
Metropolitan Transport Corporation buses ply throughout the city. These are government-run and extremely cheap. You can buy bus tickets online at redbus (http://www.redbus.in.com) or Ticketgoose (http://www.ticketgoose.com) or Via.com (http://www.via.com) . Extreme caution is advised in using these buses as they are often out of shape, will begin moving before passengers are fully boarded, and are, like second class suburban trains, notorious for passengers having to hang off the edge or outside of the bus while in motion. But now state corporation introduces New Type Deluxe, A/C Buses for Chennai Passengers. Also introduced new 2500 buses for Chennai.
By Rail
Tamil Nadu is served by Southern Railway and there are many trains from Chennai to almost every major city in India. Chennai serves as a gateway city for connections from other parts of Tamil Nadu.