Diamond Quadrilateral
high speed rail network connecting four mega cities in India
The Diamond Quadrilateral is a project of the Indian Railways to establish a high-speed rail network in India. The Diamond Quadrilateral will connect the four mega cities of India, viz. Delhi, Mumbai, Kolkata and Chennai, similar to the Golden Quadrilateral Highway system.
The High-speed train on the Mumbai-Ahmedabad section will be the first high-speed train corridor to be implemented in the country. On 9 June 2014, then President of India, Pranab Mukherjee, officially declared that the Government of India led by Prime Minister Narendra Modi will launch a Diamond Quadrilateral project of high-speed trains.
History
Prior to the 2014 general election, the two major national parties (Bharatiya Janata Party and Indian National Congress) pledged to introduce high-speed rail. The INC pledged to connect all of India's million-plus cities by high-speed rail, whereas BJP, which won the election, promised to build the "Diamond Quadrilateral" project, which would connect the cities of Chennai, Delhi, Kolkata, and Mumbai via high-speed rail. This project was approved as a priority for the new government in the incoming president's speech. Construction of one kilometer of high speed railway track will cost ₹100 crore (US$10 million) – ₹140 crore (US$15 million) which is 10-14 times higher than the cost of construction of standard railway.
India's Union Council of Ministers passed the proposal of Japan to build India's first high-speed railway on 10 December 2015.
Begin with the source’s own compact description: “Diamond Quadrilateral” is high speed rail network connecting four mega cities in India. The dossier treats that line as a proposition to test through Diamond, Quadrilateral and high, not as a finished interpretation.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Aug 20, 2026. The linked authority identifier is Q18111840. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2014 and 2015.
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This entry incorporates text from “Diamond Quadrilateral” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.