Brotton, author of A History of the World in Twelve Maps, introduces the map of the world made by the 12th-century Islamic cartographer Al-Idrisi for Roger II of Sicily. This was a masterpiece of mapping that remained the most technically sophisticated world map for 300 years after its production. Drawing on several centuries of Islamic cartographic research, Al-Idrisi produced both a book of 70 maps covering the surface of the known world, and a single, round map engraved onto a silver disk and set into a wooden table, with Mecca at its centre. The silver disk is now lost, and the Entertainment for those wanting to discover the world ('Nuzhat al-mushtāq fi'khtirāq al-āfāq'), survives only through later copies. But in a groundbreaking project, Factum Foundation has undertaken to recreate Al-Idrisi’s fabled map. Neither facsimile nor copy, this recreation nonetheless combines painstaking historical research with advanced digital techniques and the highest levels of craftsmanship, paying tribute to the lost original and offering yet another layer to add to the complexity of its transmission.