How do I reach the IIT Madras CSE department?

The CSE department is located within two interconnected buildings: the Computer Sciences Block or CSB (which includes the main CSE dept and the Computer Centre), and the second floor of the Building Sciences Block or BSB. The Department offices are located in the CSB building, whereas most of the faculty offices are in BSB.
How to reach either building depends on from which side you are coming; the best way is to ask someone in the campus for directions. Note that the entrance through the CSB block is closed after 5 PM on weekdays and throughout weekends. The BSB entrance is open 24 hours.
A map showing the location of the Department can be found here.