Grand Southern Trunk Road or National Highway 45 is an arterial road in the Indian state of Tamil Nadu.

[1] The road starts from Kathipara Junction in St Thomas Mount, Chennai towards Perambalur, Trichy, Dindigul and Theni.

It branches out from Anna Salai (previously known as Mount Road).

[2] 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.

This Indian road or road transport-related article is a stub.