Chongqing is one of China's "Three Ovens," meaning that it is one of the three hottest cities in China (the other two "ovens" are Nanjing and WuHan).

Also, most cities are abundant with bicycles. Not so with Chongqing because it is a very mountainous city and therefore, bicylces are not especially useful there. You will always be climbing and descending LOTS of stairs. Part of Chongqing is built into a cliff.

Good luck!