Natural roads (valleys, rivers, seas and oceans) constitute the structure that conditions and guarantees a series of connections that are spread in a single immense continent: Eurasia. Indeed, the history of the economic and commercial relations between east and west cannot overlook the geomorphological space that forms its material framework. As has been emphasized in numerous studies, the division of Asia and Europe is political-cultural rather than geographic-geological, Instead, it is necessary to view the Continent as a single block, bordering the Atlantic on the west, the Pacific on the east, the Arctic on the north and the Mediterranean Sea and the Indian Ocean on the south. The concept of the Silk Roads itself is a plural notion, consisting of various converging routes, such as the Spices Road, a direct link between the Mediterranean and India, or the more specific one of the Incense Road that connected the southernmost tip of the Arabian Peninsula (Oman and Yemen) with the Mediterranean basin, in use since Roman times. Many other trade routes named for a specific commodity could be added, such as those of salt, amber, and perfumes. These routes differed from each other also in terms of the means of transportation and the method of travel undertaken (by sea, caravan, mixed). Thus, even though it is often repeated that the famous Silk Road was opened around 130 BC, when the Chinese explorer Zhang Qian pushed westward for a 13-year mission (139-126 BC), a more in-depth reflection on the archaeological evidence, as well as on written and epigraphic sources, highlights how this is a misleading assumption: indeed, there has never been an era in which people have not travelled through the whole Eurasia, which has always been, culturally and technologically, interconnected.