Avadi is a City in Chennai, Thiruvallur district, Tamil Nadu, India. Its the headquarters of Avadi City Police, Avadi City Corporation and Avadi Taluk located within the Thiruvallur district of Tamil Nadu, India. Situated at about 22 kilometres (14 mi) from Chennai Central Railway Station. It is surrounded by major defence establishments and is home to various universities and engineering colleges. The neighborhood is served by Avadi Railway Station of the Chennai Suburban Railway and just 7 km from the upcoming Karayanchavadi Metro of Chennai Metro Rail. As of 2011, Avadi had a population of 345,996, which is 10th most populous place in Tamil Nadu. It is home to the Heavy Vehicles Factory (HVF), Ordnance Factory Board (ODF) which houses Engine Factory and Combat Vehicles Research and Deve...