— Nov. 5: From the GIPR, the Nizam's State Rly., and the Scindia and Dholpur Rly. (about 8690 km).
WR — Nov. 5: From the BB&CI Rly., the Saurashtra, the Rajasthan, the Jaipur, and the Cutch Rlys. (about 9120 km).
In 1952, the following zones were created:
NR — April 14: From the Jodhpur Rly., Bikaner Rly., three divisions of the East Indian Rly. north-west of Mughalsarai, and the Eastern Punjab Rly. (about 9670 km).
ER — April 14: From the rest of the East Indian Rly. (east of Mughalsarai) and the Bengal Nagpur Rly. (about 9120 km).
NER — April 14: From the Oudh-Tirhut Rly., the Assam Rly., and the Kanpur-Achnera section of the BB&CI Rly. (about 7660 km).
In 1955, the South-Eastern Railway is carved out of ER:
SER — August 1: ER retains three divisions of the old East Indian Rly. and the Sealdah division of the old Bengal-Assam Rly. (about 3740km); the rest becomes SER (about 5380km).
In 1958, the Northeast Frontier Railway was carved out of NER:
NFR — Jan. 15: the former Assam Rly. lines in the Pandu region are split off from NER to become the NFR (about 3730km).
In 1966, South-Central Rly. was carved out of SR:
SCR — Oct. 2: The former Nizam's State Rly. network (by then the Secunderabad and Solapur divisions of SR) and part of the former Madras & Southern Mahratta Rly. (by then the Vijayawada and Hubli divisions) are split off from SR to become the South-Central Rly. (about 6070km).
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