The section links to South Eastern Railway through Bokaro Steel City and Adra.

[2] Once the rail link from Howrah to Delhi was completed in 1866, the East Indian Railway was making constant endeavour to reduce the distance of the Howrah–Delhi main line.

After several surveys, one 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.

[3] The Grand Chord was opened on 6 December 1906 by Lord Minto, then Viceroy and Governor General of India with a function at Gujahandi.

[2] A repeat of the historic event was organized by East Central Railway on 6 December 2006, with a special heritage train "Grand Chord ki Rani", pulled by a 1965 steam engine, carrying the guests from Gaya to Gujhandi.

[6] In 1902, a branch line of EIR was opened from Sone East Bank (later renamed Son Nagar) to Daltonganj.

[1] Electrification of the stretch of mainline of this section from Asansol to Netaji SC Bose Gomoh was completed in 1960–61.

[7] Completion of electrification of the 97-kilometre long (60 mi) Patna–Gaya rail route before the end of 2003 was announced by the railway minister Nitish Kumar.