narrow gauge

A railroad whose track rails are closer together than the international standard of 4'8.5". Narrow gauge railroads are easier and cheaper to lay, can take tighter corners, and can economically handle lower traffic volumes than standard gauge railroads. They are popular in South America, Mexico, Japan, South Africa, Australia, New Zealand, Malaysia, and India. Some of the earliest railroads in the United States and Canada were built to narrow gauge, but were later abandoned or rebuilt to standard gauge.

The Darjeeling Himalayan railway in Nepal is narrow gauge.