Pingyao

Pingyao needs 2 days: touring the nearly intact 14th-century walls, over 6 km long, on one, and the old town with its ancient money exchange houses -forerunners of China's modern banking system-, on the other. March-May and September-November bring the mildest weather. It's inexpensive for China. It's one of the few Ming dynasty walled cities to survive China's 20th-century modernization almost entirely intact, and its Rishengchang Exchange House, founded in 1823, is considered all of China's first modern bank.