For more detailed study the cross-country line has been divided into smaller sections: The first train in India traveled from Bombay to Thane on 16 April 1853.

In Eastern India, construction of the Howrah–Delhi main line was completed and through connection between Delhi and Kolkata was established in 1865.

The opening of this track was part of the inspiration for the French writer Jules Verne's book Around the World in Eighty Days.

At the opening ceremony, the Viceroy Lord Mayo concluded that "it was thought desirable that, if possible, at the earliest possible moment, the whole country should be covered with a network of lines in a uniform system."

It is still running for 151 years as the oldest active train on this route covering 2,160-kilometre long (1,340 mi) distance in 37 hours & 30 mins with an average running speed of 57.6 kilometres per hour (35.8 mph) .

[7][8] The Kolkata–Mumbai linkage, along with other events, inspired the French writer Jules Verne to write his book Around the World in Eighty Days.