Now, each of these three mega-cities is developing commuter corridors. Little wonder: house prices in satellite towns and cities tend to be much cheaper. In Kunshan, for example, homes cost about 70% less than in nearby Shanghai. But the bullet train between the two cities takes just 19 minutes and costs a mere 25 yuan ($3.60). And Kunshan is just one of many options for those seeking to escape Shanghai's high costs. There are now about 75 million people living within an hour of Shanghai by high-speed rail.
Surveys show that more than half of passengers on the busiest lines are "generated traffic"—that is, people making trips that they would not have made before. This is unquestionably good for the economy. It means the trains are expanding the pool of labour and consumers around China's most productive cities, while pushing investment and technology to poorer ones. Xu Xiangshang, a dapper businessman, oversees sales of apartments built next to high-speed railway stations in less well-off parts of Anhui. These are less than half an hour from Nanjing, a prosperous city of 8m that is the capital of Jiangsu province. "Bullet trains are becoming just like buses," he says.