The best time to visit Shanghai is early fall, when the weather is good and crowds diminish. Although temperatures are scorching and the humidity can be unbearable, summer is the peak tourist season, and hotels and transportation can get very crowded. If possible, book several months in advance for summer travel.
Avoid the three national holidays: Chinese New Year, which ranges from mid-January to mid-February; the Labor Day holiday during the first week of May; and the National Day holiday during the first week of October. Imagine 1.2 billion people on the move, and you'll understand why it isn't a good time to travel.
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