A broad-gauge railway is a railway with a track gauge broader than the 1,435 mm (4 ft 8 1 ⁄ 2 in) standard-gauge railways.. Initially introduced in Europe, broad gauge has given way to standard gauge in most of the Europe and Americas. Broad gauge of 1,524 mm (5 ft), commonly known as Russian gauge, is the dominant track gauge in former Soviet Union (CIS states, Baltic states, Georgia and ...