Grand Southern Trunk Road
| Grand Southern Trunk Road | |
|---|---|
| மாபெரும் தெற்கு வழித்தடம் | |
| GST Road Chennai–Trichy–Dindigul Road Former National Highway 45 | |
 Route of the former National Highway 45 | |
| Location | |
| Country | India |
| States | Tamil Nadu |
| Highway system | |
The Grand Southern Trunk Road (GST Road) is a historic major arterial road in the Indian state of Tamil Nadu, forming one of the principal southern road corridors from Chennai. The route developed as part of the trunk-road network established under the Madras Presidency; systematic construction of trunk roads by the colonial government began after the creation of the Trunk Road Department in 1845, following earlier efforts to improve roads for military and commercial purposes.[1] The southern trunk corridor subsequently linked Madras with inland centres including Tiruchirappalli, and sections of the route later formed part of National Highway 45 (NH 45).[2]
Following the national-highway renumbering introduced with effect from 5 March 2010, the former NH 45 corridor was divided among several newly numbered national highways.[3] The Chennai–Tindivanam section now forms part of National Highway 32, although official road records and common usage continue to identify it as the GST Road or as the former NH 45.[4][2] Through the Chennai metropolitan area, the road passes through Guindy, Meenambakkam, Pallavaram, Chromepet, Tambaram, Vandalur and Chengalpattu before continuing towards Tindivanam.
Colonial period
[edit]The route developed from earlier military and commercial roads linking Madras with the southern districts of the Madras Presidency. Systematic construction and maintenance of trunk roads began in 1845 with the creation of the Trunk Road Department, which placed the Madras–Trichinopoly road among the presidency's principal lines of communication.[5]
During the mid-nineteenth century, the colonial government progressively improved these trunk routes for military movement, administration and commercial traffic. The southern route from Madras subsequently developed into the principal trunk road towards Trichinopoly and the southern Presidency, forming the historical predecessor of the modern Grand Southern Trunk Road.[6]
Major junctions
[edit]From north to south, major junctions along the GST Road include:
- Kathipara Junction – connection with Mount-Poonamallee Road and the Chennai Airport corridor
- St. Thomas Mount – Mount–Medavakkam High Road
- Pallavaram – Pallavaram–Kundrathur–Poonamallee Road and Pallavaram–Thuraipakkam Radial Road
- Tambaram – Tambaram–Velachery Road and Tambaram–Mudichur Road
- Irumbuliyur – Chennai Bypass Road
- Vandalur – Chennai Outer Ring Road and Vandalur–Kelambakkam Road
- Guduvancheri – Guduvancheri–Thiruporur Road
- Singaperumal Koil – Singaperumal Koil–Sriperumbudur Road
- Chengalpattu – connections towards Thiruporur and Mamallapuram
The Chengalpattu district administration identifies GST Road, the Outer Ring Road, Vandalur–Kelambakkam Road, Pallavaram–Thuraipakkam Radial Road, Pallavaram–Kundrathur–Poonamallee Road and several of the connecting roads above as major road links in the district.[7]
Infrastructure developments
[edit]The GST Road corridor has undergone successive widening and grade-separation works as traffic and suburban development have increased. By 2024, the National Highways Authority of India had widened about 18.5 kilometres (11.5 mi) of the Vandalur–Chettipunniyam section from four to eight lanes.[8]
A proposed six-lane elevated corridor of about 18.4 kilometres (11.4 mi) between the Kalaignar Centenary Bus Terminus and Chettipunniyam near Mahindra World City is intended to reduce congestion on the Tambaram–Chengalpattu stretch. As of September 2025, the detailed project report had been finalised, with tendering dependent on coordination with the proposed Airport–Kilambakkam Metro alignment.[8]
The older Palar bridges near Mamandur were strengthened and repaired in 2022 after deterioration of expansion joints caused major traffic diversions. The first bridge reopened in February 2022, followed by repairs to the parallel bridge.[9]
Road-safety improvements have also continued at accident-prone locations along national highways in Tamil Nadu, including measures such as flyovers, underpasses, pedestrian crossings, illumination and junction improvements.[10]
References
[edit]- ↑ "Transport and Communication". Madras City Report, Census of India 1961 (PDF) (Report). Office of the Registrar General, India. Retrieved 21 September 2026.
- 1 2 State Highways – Chennai City Roads Division (PDF) (Report). Highways Department, Government of Tamil Nadu. Retrieved 21 September 2026.
- ↑ "Notification S.O. 689(E): Old and new National Highway numbers" (PDF). Ministry of Road Transport and Highways, Government of India. 4 April 2011. Retrieved 21 September 2026.
- ↑ Completed Projects (PDF) (Report). National Highways Authority of India. Retrieved 21 September 2026.
- ↑ "Transport and Communication". Madras City Census Report 1961 (PDF) (Report). Office of the Registrar General, India. Retrieved 21 September 2026.
- ↑ Proceedings of the Twenty-Fourth Annual Session of the Tamil Nadu History Congress (PDF). Tamil Nadu History Congress. 2004. Retrieved 21 September 2026.
- ↑ "About District". Chengalpattu District, Government of Tamil Nadu. Retrieved 21 September 2026.
- 1 2 "KCBT-Chettipunniyam 18-km elevated stretch to ease congestion on GST road". The New Indian Express. 8 September 2025. Retrieved 21 September 2026.
- ↑ "Tamil Nadu: NHAI repairs Palar bridge ahead of schedule". The Times of India. 23 February 2022. Retrieved 21 September 2026.
- ↑ "Only 46% funds allocated to fix black spots on national highways in TN utilised". The New Indian Express. 23 July 2026. Retrieved 21 September 2026.
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