When the northern Toba Wei invaders decided to move their capital from Datong into the Chinese heartland, Luoyang was the site they chose probably because it was believed to be the centre of the world ( a belief based on the shadow cast by the sun at summer solstice at nearby Yangcheng observatory). In 493, at the command of emperor Xiao Wendi, they moved almost overnight to Luoyang and constructed a new capital. In 30 years it had grown to a city of half a million people with markets selling goods from all over Asia and more than 1400 Buddhist temples. The great carvings of Longmen were begun in this period. In 534, at the command of another Wei emperor and even more suddenly than it had been taken up, Luoyang was again abandoned and its people, including the residents of all the temples, were forced to move to Yeh. An account written 13 years later described the city walls as collapsed and overgrown with artemisia, the streets full of thorn trees and millet planted between the ceremonial towers of the ruined palace.

Luoyang lay in ruins once more for 70years until under the Sui dynasty, it was rebuilt west of the Wei ruins on a grid pattern spreading across both banks of the Luo river. Two million men were conscripted for the work and the new city rapidly became the most important market centre in China, a magnet for foreign traders with a population of a million, three separate major markets within the walls, over 3000 shops and stalls and around 400 inns for merchants. To feed the crowds, grain was brought up the Grand canal from the Yangzi basin and stored in enormous barns: the Hanjia granary, discovered in 1971 west of the old city, held 250,000 metric tons and was proof against damp, mildew, rats and insects. The emperor Yang Di also brought 3000 musicians to live at his court and surrounded himself with scholars, scientists and engineers.