Starting with the Tōkaidō Shinkansen (515.4 km, 320.3 mi) in 1964, the network has expanded to currently consist of 2,764.6 km (1,717.8 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 (80 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, and Hakodate on northern island of Hokkaido, with an extension to Sapporo under construction and scheduled to commence in March 2031. The maximum operating speed is 320 km/h (200 mph) (on a 387.5 km section of the Tōhoku Shinkansen). Test runs have reached 443 km/h (275 mph) for conventional rail in 1996, and up to a world record 603 km/h (375 mph) for SCMaglev trains in April 2015.
The original Tōkaidō Shinkansen, connecting Tokyo, Nagoya and Osaka, Japan’s three largest cities, is the world's busiest high-speed rail line. In the one-year period preceding March 2017, it carried 159 million passengers, and since its opening more than five decades ago, it has transported more than 5.6 billion total passengers The service on the line operates much larger trains and at higher frequency than most other high speed lines in the world. At peak times, the line carries up to thirteen trains per hour in each direction with sixteen cars each (1,323-seat capacity and occasionally additional standing passengers) with a minimum headway of three minutes between trains.
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 the Chinese high-speed railway network surpassed it at 370 million passengers annually, reaching over 1.7 billion annual passengers in 2017, though the total cumulative passengers, at over 10 billion, is still larger. While the Shinkansen network has been expanding, Japan's declining population is expected to cause ridership to decline over time. The recent expansion in tourism has boosted ridership marginally.
Shinkansen (Japanese: 新幹線) in Japanese means new trunkline or new main line, but the word is used to describe both the railway lines the trains run on and the trains themselves. In English, the trains are also known as the bullet train. The term bullet train (Japanese: 弾丸列車,Hepburn: dangan ressha) originates from 1939, and was the initial name given to the Shinkansen project in its earliest planning stages. Furthermore, the name superexpress (Japanese: 超特急,Hepburn: chō-tokkyū), used exclusively until 1972 for Hikari trains on the Tōkaidō Shinkansen, is used today in English-language announcements and signage.