The New DelhiâÂÂChennai line, earlier known as DelhiâÂÂMadras line, is an Indian railway line connecting New Delhi and Chennai Central. It is one of the seven major trunk routes of the Indian Railways. It traverses about across the states of Delhi, Haryana, Uttar Pradesh, Rajasthan, Madhya Pradesh, Maharashtra, Telangana, Andhra Pradesh, and Tamil Nadu. The line forms part of the planned Diamond Quadrilateral rail network. The route is used by the Grand Trunk Express and as such is referred to as the Grand Trunk Route.
The AgraâÂÂDelhi chord was opened in 1904. Some parts of it were relaid during the construction of New Delhi (inaugurated in 1927âÂÂ28).
The AgraâÂÂGwalior line was opened by the Maharaja of Gwalior in 1881 and it became the Scindia State Railway.
The Indian Midland Railway built the GwaliorâÂÂJhansi line and the JhansiâÂÂBhopal line in 1889.
The BhopalâÂÂItarsi line was opened by the Begum of Bhopal in 1884. Itarsi was linked with Nagpur between 1923 and 1924.
The period of construction of the NagpurâÂÂBalharshah line is uncertain.
The VijayawadâÂÂMadras line was constructed in 1899.
The WadiâÂÂSecunderabad line was built in 1874 with financing by the Nizam of Hyderabad. It later became part of Nizam's Guaranteed State Railway. In 1889, the main line of the Nizam's Guaranteed State Railway was extended to Vijayawada, then known as Bezwada.
With the completion of the KazipetâÂÂBalharshah link in 1929, Madras was directly linked to Delhi.
The -long trunk line, amongst the long and busy trunk lines connecting the metros, has been treated in more detail in smaller sections:
The VijayawadaâÂÂMadras section electrified by 1980.
The VijayawadaâÂÂKazipet sector was electrified in 1985âÂÂ88.
The KazipetâÂÂRamagundamâÂÂBalharshahâÂÂNagpur sector was electrified in 1987âÂÂ89.
The BhopalâÂÂItarsi sector was electrified in 1988âÂÂ89 and the NagpurâÂÂItarsi sector in 1990âÂÂ91.
The AgraâÂÂBhopal sector was electrified in 1984âÂÂ89.
The AgraâÂÂFaridabad section was electrified in 1982âÂÂ85.
The DelhiâÂÂChennai line (Grand Trunk route) is classified as a "Group A" line which can take speeds up to 160 km/h.
New Delhi, Mathura Junction, Agra Cantt., Gwalior, Jhansi, Bhopal, Rani Kamalapati, Itarsi, Nagpur, Ramagundam, Warangal, Vijayawada, Gudur and Chennai Central, on this line, are amongst the top hundred booking stations of Indian Railway.
The DelhiâÂÂChennai line is a part of the diamond quadrilateral. The routes connecting the four major metropolises (New Delhi, Mumbai, Chennai and Kolkata), along with their diagonals, known as the diamond quadrilateral, carry about half the freight and nearly half the passenger traffic, although they form only 16 per cent of the length.