A narrow-gauge railway track has a width of 2 feet 6 inches, which equals 762 mm.
Indian Railways uses different track widths, known as gauges, based on terrain and traffic needs. Broad gauge measures 1676 mm and is the most common in India. Metre gauge measures 1000 mm. Narrow gauge, at 762 mm, is the smallest of the widely used gauges and is mainly built in hilly or difficult terrain where a wider track is not practical.
Famous narrow-gauge lines in India include the Kalka-Shimla Railway and sections of the Darjeeling Himalayan Railway, both known for their scenic hill routes.