In 2008,the IR operated 11,106 km of rail with a further 18,900 km in various stages of development.[15]Almost all of this is standard gauge of 1,435 mm (4 ft 8 1⁄2 in),but 94 km are Russian gauge of 1,520 mm (4 ft 11 27⁄32 in)to link up to ex-Soviet Union border states.There is also the no-longer-isolated Indian gauge section of 1,676 mm (5 ft 6 in) from Zahedan to the Pakistan border that continues to Quetta and the Indian sub-continent.The extent of double-track lines is 1,082 km.The Jolfa–Tabriz line is electrified(148 km).In 2006,IR reported that it possessed 565 engines,1,192 passenger coaches,and 16,330 wagons.The vast majority of the engines are diesel-powered.