High-speed rail
High-speed rail is a type of rail transport that operates significantly faster than traditional rail traffic, using an integrated system of specialized rolling stock and dedicated tracks. While there is no single standard that applies worldwide, new lines in excess of and existing lines in excess of are widely considered to be high-speed, with some extending the definition to include lower speeds in areas for which these speeds still represent significant improvements. The first such system began operations in Japan in 1964 and was widely known as the bullet train. High-speed trains normally operate on standard gauge tracks of continuously welded rail on grade-separated right-of-way that incorporates a large turning radius in its design.
High-speed rail in China
The grid is composed of eight high-speed rail corridors, four running north-south and four east-west, and has a total of 12,000 km. Most of the lines follow the routes of existing trunk lines and are designated for passenger traffic only. They are known as passenger-designated lines (PDL). Several sections of the national grid, especially along the southeast coastal corridor, were built to link cities that had no previous rail connections. Those sections will carry a mix of passenger and freight. High-speed trains on HSR Corridors can generally reach . On mixed-use HSR lines, passenger train service can attain peak speeds of . This ambitious national grid project was planned to be built by 2020, but the government's stimulus has expedited time-tables considerably for many of the lines.