Grand Southern Trunk Road

Grand Southern Trunk Road or National Highway 45 is an arterial road in the Indian state of Tamil Nadu. It is also known as Chennai–Trichy-Dindigul-Theni Highway. The road starts from Kathipara Junction in St Thomas Mount, Chennai towards Trichy, Dindigul and Theni. It branches out from Anna Salai (previously known as Mount Road).

The road runs through important localities like Meenambakkam, Pallavaram, Kadaperi, Tambaram, Vandalur, Kilambakkam, Guduvanchery, Paranur, Chengalpattu, Madurantakam, Tindivanam, Villupuram, Vikravandi, Ulundurpet, Perambalur, Trichy, Dindigul, and Theni.

Major junctions
Chennai City Outside Chennai
 * Mount-Poonamallee Road near Kathipara Junction
 * Mount-Medavakkam High Road in St.Thomas Mount
 * Pallavaram-Kundrathur-Poonamallee Road (Pammal Main Road) in Pallavaram
 * Pallavaram-Thiruneermalai Road in Pallavaram
 * Pallavaram-Thuraipakkam Radial Road in Pallavaram
 * Chitlapakkam and Hasthinapuram Main Road near MIT Bridge Along GST Road
 * Gandhi Road in Tambaram
 * Velachery Main Road and Mudichur Road in Tambaram
 * Chennai Bypass Road in Irumbuliyur
 * Chennai Outer Ring Road in Vandalur
 * Vandalur-Kelambakkam Road in Vandalur
 * Guduvancheri Tiruporur road
 * Kotteripattu Near Tindivanam

Developments

 * 1) NHAI to repair Palar Bridge in Grand Southern Trunk Road near Chengalpattu.
 * 2) Double Deck Structure proposed between Airport and Irumbuliyur along GST Road.
 * 3) NHAI set to rectify 18 accident-prone spots in GST Road.