This is the laying of the Rail Network set up in East India between 1854 & 1929 . I noted this information from Rail Bandhu Magazine during my journey on board the HWH Raj Exp via PNBE :-
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Section & it's year of Introduction are as follows :-
Delhi - Mughalsarai -> 1866
Mughalsarai...
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- Patna -> 1862
Patna - Luckeesarai -> 1865
Luckeesarai - Jamalpur -> 1862
Jamalpur - Bhagalpur -> 1862
Bhagalpur - Sahibganj -> 1861
Sahibganj - Sainthia -> 1860
Sainthia - Burdwan -> 1859
Burdwan - Howrah (Via Bandel) -> 1854
Mughalsarai - Gaya -> 1900
Gaya - Luckeesarai -> 1879
Luckeesarai - Madhupur - Sitarampur -> 1871
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Gaya - Patna -> 1899
Gaya - Dhanbad -> 1906
Sonnagar - Daltonganj -> 1902
Daltonganj - Barkakhana -> 1929
Barkakhana - Dhanbad -> 1927
Dhanbad - Barakar -> 1894
Barakar - Sitarampur -> 1865
Sitarampur - Andal -> 1863 - 65
Andal - Khana Jn -> 1855
Khana Jn - Pundooah (Now Pandua) -> 1855
Pundooah - Bandel - Hooghly -> 1854
Hooghly - Sheoraphuli - Howrah -> 1854
Khana Jn - Sheoraphuli - Howrah (Via Liluah) -> 1917
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LOCAL Routes are as follows :-
Andal - Sainthia -> 1908
Sheoraphuli - Tarakeshwar -> 1885
Madhupur - Giridih -> 1871
Barhawara - Azimganj - Katwa -> 1913
Nalhati - Azimganj -> 1863
Ahmadnagar - Katwa (NG) -> 1917
Katwa - Burdwan (NG) -> 1915
Bhagalpur - Mandarhil -> 1926
Jamalpur - Munger -> 1862