SDAH NDLS Duronto: দৌঁড়ে চলো , দিল্লি চলো - PPG

Longest passenger trains in the world (Length )
Australia – up to 99 coaches (approximately 1.2 km) on The Ghan

Japan - Tōkaidō Shinkansen N700 16-car trainset 404 m
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the Netherlands – up to 15 coaches (five 3-coach NS Intercity Materieel trains combined)[16] – 403 m

Sweden – 17 coaches (26.7 m each plus two Rc locomotives at 15.4 m) – 484 m between Stockholm and Luleå. Sometimes charter trains are longer than that. E.g. 22 coaches, 530 m on 24-25 Febr 2012.[17]

Germany – two ICE 3 trains combined – 402 m

France – two TGV Atlantique trains combined – 476 m

United Kingdom, Belgium, France – Eurostar / British Rail Class 373 (20 cars multiple unit) – 394 m

United States — Auto Train between Lorton, Virginia, and Sanford, Florida — up to 49 cars. 4 coaches, 2 lounges, 3 diners, 6 sleepers, one transition sleeper and up to 33 autoracks.

United States - Ringling Bros. and Barnum & Bailey Circus trains - Longest privately operated passenger trains in the world at nearly sixty cars each. Two trains, the Red unit and the Blue unit, tour the country in an overlapping two-year cycle. Each circus train consists of around 40-45 passenger cars with dorm rooms for the circus performers and crews, four animal cars usually placed at the front of the train for a smoother ride, a dining car referred to as the "pie car," a generator car to provide power to the train, two merchandise boxcars and 15-20 flatcars carrying circus vehicles and containers.

India - 24 coach trains are standard for most popular long distance services, which translates into approximately 600 meters per train.

Canada - The Canadian transcontinental train may have 33 train cars during peak season (May to September)
The length of passenger trains generally has to match the length of platforms, especially high-level platforms. These platforms cannot always be extended to suit extended train lengths due to bridges, tunnels, pointwork, narrowing track centers and stabling yards, though "selective door opening" can help long trains stop at short platforms.