The Nepal-Janakpur Railway, otherwise known as the Janakpur Railway was reportedly opened 1937. The line was a 2ft 6in/762mm narrow gauge(NG) railway constructed by the British in 1937. The 28-mile-long (45 km) track was built to carry timber from the then heavily forested areas of Janakpur in Kingdom of Nepal to Jaynagar in British India. The railway was later extended from Janakpur to Bijalpura, a further 21km 
An alternative account gives the date of opening as 1928 with the following comment
The line connects Jaynagar (India) to Janakpur Nepal), a distance of 32km, an important Nepalese pilgrimage site, about 100 km south-east of Kathmandu. From Janakpur the line continues to Bijalpura. .
The operating company "Transport Corporation of Nepal - Janakpur Railway" was renamed to "Nepal Railways Corporation Ltd." in 2004, but is still a state-owned enterprise.
After a washout of the railway embankment and two bridges the track between Janakpur and Bijalpura (22 km railway line) was closed in 2001. The remaining Janakpur–Jaynagar railway track was converted to 5 ft 6 in (1,676 mm) broad gauge in 2018 and the extension to Bardibas is under construction .