The City of Light or The City Of Light: The Hidden Journal of the Man Who Entered China Four Years Before Marco Polo is a book purportedly made by a scholarly Jewish merchant called "Jacob d'Ancona" who wrote in vernacular Italian, an account of a trading venture he made, in which he reached China in 1271, four years before Marco Polo.

[3] T. H. Barrett, School of Oriental and African Studies, in The London Review of Books, 30 October 1997, described the text as a forgery; he noted that the garbled name Baiciu for a famous rebel "was only known to the narrator of the account in a form which derived from an 18th-century misreading of an Arabic manuscript— as good a proof as any that something is badly amiss.

Bernard Wasserstein, president of the Oxford Center for Hebrew and Jewish Studies, and his brother, David, professor of Islamic history at Tel Aviv University publicly called attention to an anachronism, Jacob's arrival at a mellah in the Persian Gulf, a descriptive for a ghetto based on the root for "salt", that was not used until the 15th century, in Morocco.

[3] In 2018, Stephen G. Haw, writing in the Journal of the Royal Asiatic Society, considered the book to be a modern forgery and cited many issues with the accuracy of the text.

Haw concludes "My own final judgment of Jacob d’Ancona’s The City of Light is that it is an obvious forgery, fabricated by someone with only a very superficial knowledge of Chinese history, culture, and language.