The Shinkansen (???, new trunk line) is a network of high-speed railway lines in Japan operated by four Japan Railways Group companies. Starting with the T?kaid? Shinkansen (515.4 km) in 1964, the network has expanded to currently consist of 2,387.7 km (1,483.6 mi) of lines with maximum speeds of 240–320 km/h (150–200 mph), 283.5 km (176.2 mi) of Mini-shinkansen lines with a maximum speed of 130 km/h (81 mph), and 10.3 km (6.4 mi) of spur lines with Shinkansen services. The network presently links most major cities on the islands of Honshu and Kyushu, with construction of a link to the northern island of Hokkaido underway.
The maximum operating speed is 320 km/h (200 mph) (on a 387.5 km section of the T?hoku Shinkansen). Test runs have reached 443 km/h (275 mph) for conventional rail in 1996, and up to a world record 581 km/h (361 mph) for maglev trainsets in 2003.
Shinkansen literally means new trunk line, referring to the high-speed rail line network. The name Superexpress (??? ch?-tokky?), initially used for Hikari trains, was retired in 1972 but is still used in English-language announcements and signage.
The T?kaid? Shinkansen is the world's busiest high-speed rail line. Carrying 151 million passengers per year (March 2008), it has transported more passengers (over 5 billion, entire network over 10 billion) than any other high-speed line in the world. Between Tokyo and Osaka, the two largest metropolises in Japan, up to thirteen trains per hour with sixteen cars each (1,323 seats capacity) run in each direction with a minimum headway of three minutes between trains. Though largely a long-distance transport system, the Shinkansen also serves commuters who travel to work in metropolitan areas from outlying cities. Japan's Shinkansen network had the highest annual passenger ridership (a maximum of 353 million in 2007) of any high-speed rail network until 2011, when China's high-speed rail network surpassed it at 370 million passengers annually.