Chinese has a radically different phonology from European languages, in which the phonological values which correspond to sounds, either consonants or vowels, from European languages don't make much sense.

Previous geographical names such as "Peking" for "Beijing", and "Canton" for "Guangzhou" simply represent an earlier attempt at romanization efforts, to allow Europeans to pronounce Chinese names of cities to at least a passing resemblance.

Another hurdle is that there are many different dialects of a Chinese language, and even multiple Chinese languages among which the only connection is their mutual written intelligibility through Chinese Characters and their belonging to the same language family. For example, Mainland China usually speaks Mandarin, and Hong Kong usually speaks Cantonese. Taiwanese is similar to Mandarin, but still different. There are also other languages in the country, like Wu. To a degree, even traditional Korean and Japanese is intelligible through written Chinese because of the large mutual cultural and linguistic influences, despite belonging to radically different language families. (Korean and Japanese for example might have more in common with Mongolian, Turkish, and Hungarian, than with Chinese).