Anna Salai (Tamil: [aɳɳaː saːlaɪ]), formerly known as St. Thomas Mount Road or simply Mount Road, is an arterial road in Chennai, India. It starts at the Cooum Creek, south of Fort St George, leading in a south-westerly direction towards St. Thomas Mount, and ends at the Kathipara Junction in Guindy. Beyond the Kathipara Junction, a branch road arises traversing westwards to Poonamallee to form the Mount-Poonamallee Road while the main branch continuing southwards to Chennai Airport, Tambaram and beyond to form Grand Southern Trunk Road (GST Road or NH45). Anna Salai, which is more than 400 years old, is acknowledged as the most important road in Chennai city. The head offices of many commercial enterprises and public buildings are located along Anna Salai. It is the second longest road in