A 336 km metre-gauge line of the North Bengal Railway linked Saraghat on the northern bank of the Padma to Siliguri.

In 1926 the metre-gauge section north of the bridge was converted to broad gauge, and so the entire Calcutta – Siliguri route became broad-gauge.

[2] The Siliguri–Haldibari, part of the original broad gauge Calcutta–Siliguri track via Hardinge Bridge, got delinked from the trunk route in 1947.

[2] In the joint statement issued on the occasion of the visit of the Prime Minister of India to Bangladesh, on 7 September 2011, it was stated: "Bangladesh Prime Minister expressed her appreciation to the Indian Prime Minister for amendment of the MoU between the Bangladesh and Indian Railways allowing Rohanpur-Singabad as an additional route for both bulk and container cargo for Nepalese rail transit traffic.

They also agreed to re-establish rail connections between Chilahati–Haldibari and Kulaura–Mahishashan in the spirit of encouraging revival of old linkages and transport routes between the two countries.