China has seen a lot of cities growing bigger from 1992 to 2015 due to economic growth. The speed of city expansion changed over time, with a big increase from 2000 to 2010. Coastal and capital cities grew a lot, while cities in central and northern areas also got bigger after 2010. Population size was a big factor in city growth, but not the only one. Economic factors didn't play a big role, except in the west. Different regions need different policies to manage city growth, especially in ecologically sensitive areas. It's important to focus on the quality of land in cities to slow down city expansion.