Although the construction of China’s high-speed rail (HSR) network only started in 2003, the network is already the largest in the world.

Researchers from Institute of Geographic Sciences and Natural Resources Research (IGSNRR)，Chinese Academy of Sciences, employ three indicators of accessibility, and analyses three Scenarios to analyse the impact of the evolving HSR network on the accessibility by HSR and conventional ground transport of 333 prefecture-level cities and 4 municipalities.

The study shows that the HSR network will bring about substantial improvement in accessibility, and lead to national time-space convergence, but will also increase the inequality of nodal accessibility between eastern, central, and western regions, between cities with different sizes of population and between cities that differ in the shortest distance to HSR stations.

The HSR network enlarges internal disparities in each of the regions and the five types of cities. The internal inequality of nodal accessibility in all three Scenarios generally increases from the eastern region via the central region to the western region, as well as from very large cities to small cities, varying inversely with the level of economic development and population size. Spatially, accessibility increases generally conform to the distance decay rule but with minor fluctuations.

The 50 cities with the largest increases in accessibility are mostly located 50 km or less away from HSR stations and have populations of over 3 million, with the smaller ones located along HSR lines or around large cities such as Beijing, Shanghai, and Guangzhou. As time progresses, the planned HSR network will result in more balanced development, but regional disparities in accessibility will still be greater than before the construction of the HSR.

The related result has been published in the Journal of Transport Geography(Jiao J., Wang J.*, Jin F, et al. Impacts on accessibility of China’s present and future HSR network. Journal of Transport Geography. http://dx.doi.org/10.1016/j.jtrangeo.2014.07.004 ).