Tamil Nadu Express - எங்கள் உயிர் துடிப்பு - Vijay Baradwaj

IN the wikipage for Indian railways its mentioned that thre are 4 types of guage in India. I quote "Indian railways uses four gauges, the 1,676 mm (5 ft 6 in) broad gauge which is wider than the 1,435 mm (4 ft 8 1⁄2 in) standard gauge; the 1,000 mm (3 ft 3 3⁄8 in) metre gauge; and two narrow gauges, 762 mm (2 ft 6 in) and 610 mm (2 ft) ."
Can some one tell me where the standard guage is used?

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