China's high-speed rail (HSR) system started construction in the early 2000s. By the end of 2020, high speed rail in China had reached  of dedicated lines alone, making it the longest HSR network in the world. Services on the Beijing–Shanghai, Beijing–Tianjin, and Chengdu–Chongqing Lines reach up to , making them the fastest conventional high speed railway services in the world. With an annual ridership of over 2.29 billion passengers in 2019 it is the world's busiest. The network includes the Beijing–Guangzhou–Shenzhen High-Speed Railway, the single longest HSR line in the world, and the Beijing–Shanghai High-Speed Railway, which has three of longest railroad bridges in the world. The Shanghai Maglev Train, which reaches , is the fastest commercial train service in the world.