Railways are divided into three categories: Broad gauge: The distance between rails is 1.676 metre. The total route length of broad gauge is 54,257 km which accounts for 84.81 percent of the total length of rail route in the country. Almost all the main routes are broad gauge. Broad gauge system links major ports of India with the interior towns and industrial centres and handles 85 percent of the total goods traffic in terms of tonnes-km. It is also called India gauge.The Konkan railway line, a broad gauge railway on the west coastal lowland , is an engineering marvel of the Indian Railways. Metre gauge: The distance between rails is one metre. It covers 7,180 km and accounts for 11.22 percent of the total route length. Narrow gauge: The distance between rails is 0.762 metre and 0.610 metre. It covers 2537 km and accounts for 3.96 percent of the total route length. It is mainly confined to the hilly areas.