The vast majority of rapid transit systems use 1,435 mm (4 ft 8+1⁄2 in) standard gauge. Some of the largest and oldest subway systems in the world use standard gauge in agreement with the country wide dominant usage for track gauge, e.g. London Underground (1863), Chicago "L" (1892), Vienna Metro (1898), Paris Métro (1900), Berlin U-Bahn (1902), New York City Subway (1904), Stockholm Metro (1950), Milan Metro (1964), Mexico City Metro (1969), Beijing Subway (1971), Seoul Metropolitan Subway (1974), Shanghai Metro (1993), Guangzhou Metro (1997), Shenzhen Metro (2004). Many rapid transit systems in countries where the main lines do not use standard gauges are built in standard gauge, including the Barcelona Metro, Santiago Metro, Taipei Metro, and many systems in India.