Indian Railways: Indian Railways (IR) is among the top 5 biggest railway networks in the world as it manages a very heavy railway traffic and millions of passengers daily. The Indian Railways manages more than 7308 stations that cater to about 13000 trains daily carrying upwards of 20 million passengers. Indian Railways is one of the biggest sources of revenue for the government making it the backbone of the Indian economy. IR is one of the most popular preferred and cheapest modes of transport in the country. Some of the most popular and important trains run by Indian Railways include the Rajdhani Express Shatabdi Express Duronto Express Vande Bharat Express Garib Rath Express Gatimaan Express and Tejas Express. The history of Indian Railways is more than 160 years old as the first passenger train in India ran from Mumbai to Thane on April 16 1853. This marked the beginning of Indias extensive railway network which is now the fourth-largest rail network in the world. Here we will tell you about the oldest running passenger train in India. Its name is Howrah-Kalka Mail and it has been in service for 158 years. It connects Howrah in Kolkata the capital of West Bengal to Kalka town in the Panchkula district of Haryana. The Howrah-Kalka Mail first ran on January 1 1866 and initially ran between Howrah and Delhi and was later extended from Delhi to Kalka in 1891. The name of this has been changed three times. First it was called East India Railway Mail which was later renamed to Kalka Mail. It is believed that Netaji Subhas Chandra Bose boarded this train from Gomoh in the Dhanbad district to evade the British in 1941. The Howrah-Kalka Mail was renamed Netaji Express in 2021 on the 125th birth anniversary of Netaji Subhas Chandra Bose.