Gaya–Pandit Deen Dayal Upadhyaya Junction section
The Gaya–Pandit Deen Dayal Upadhyaya Junction section, formerly Gaya–Mughalsarai section , is a railway line connecting Gaya Junction and Pandit Deen Dayal Upadhyaya Junction. This track is part of the Grand Chord, Howrah–Gaya–Delhi line and Howrah–Prayagraj–Mumbai line. This section includes Arrah-Sasaram and Son Nagar branch lines. It is under the jurisdiction of East Central Railway.
Grand Chord
Ever since the railway connection of Delhi with Howrah in 1866, the East Indian Railway Company was making regular efforts to reduce the distance of the Howrah–Delhi main line. After a survey in 1888-89 and two more subsequently, a route was determined from Dhanbad to Mughal Sarai via Koderma and Gaya. The major works in this section were a bridge across the Son River at Dehri, and tunnelling and ghat line construction between Gurpa and Gujhandi. The Grand Chord was opened in 1907. Even when the Grand Chord was under construction, the Son Nagar-Daltonganj branch line was opened in 1902.Bridging the Soane/Son
The total length of the Upper Sone Bridge across the Soane, as the river was then called, over abutments is. It was opened for traffic on 27 February 1900. When it was built, it was the longest bridge in India and was believed to be the second longest bridge in the world, short of the Tay Bridge near Dundee. Subsequently, longer road bridges were built but it remained the longest rail bridge in India for many years. The opening of the 4.62 km Vembanad Rail Bridge, connecting the Container Transshipment Terminal on Vallarpadam Island to Edappally, in February 2011, pushed it to the second position.Electrification
The Gaya–Pandit Deen Dayal Upadhyaya Junction section was electrified in 1962.In 1965, Asansol–Bareilly Passenger was the first long-distance train on Eastern Railway hauled by an AC loco.