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Another official account of a Hyderabad-Gadag link dating from April, 1913. By this time, the idea of a Wadi-Gadag line seems to have been abandoned to avoid the break of gauge at Wadi, and instead, a Hyderabad-Gadag line was surveyed by the Nizam's State railway.
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They mention that surveys were being done/completed for a line from SC to Krishna (near present-day Gadwal), Krishna to Raichur, Raichur to Hatti and onward to Gadag via Lingsugur. Construction for this line was started from the SC end by...
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the Nizam's railway. during WW1, the line till MBNR was completed and the rest of the plan was abandoned to focus on other BG routes. Further construction only happened in bits and reaching Gadwal on July 20th, 1925. At this point, as the MG route from Gadag to KRNT was already available, the final section was constructed between KRNT-Gadwal and the remaining lines were dropped. In fact, this was among the last MG links constructed by the Nizam.