One of the earliest Eurasian travelers whose itinerary can be traced in detail[1] is a Chinese Buddhist monk named Xuanzang, who lived in the seventh century CE. Xuanzang is remarkable not only as a traveler but also as a translator. Buddhism is a religion (or philosophy) with a very extensive corpus of sacred writings. It is native to India rather than China, and the earliest missionaries to enter China did not bring with them the full body of holy writings. Xuanzang's great journey was to travel to India to study and acquire Buddhist texts; and his great achievement was to translate them from their original Sanskrit into Chinese upon his return.
The team that constructed this site made a collective attempt to map Xuanzang's travels at an early stage of our work, in part as a way of discovering the challenges we would face as we each aimed to follow a given traveler's journey for the project. Among the problems we discovered were that the most recent translation available to us[2] gave many place names that could not easily be identified, either because we could not find a place of that name at all, or because the location was only vaguely described in the original source ("then we passed through the country of..." or "we crossed the such-and-such river", without any indication of what parts of the country were visited or where the river was crossed). It was always our hope to return to Xuanzang after we had gotten more practice with other travelers, but the semester drew to a close before we had the time to dedicate to it.
In place of our own map and study, we are happy to say that there is a Google Arts and Culture project on Xuanzang at https://artsandculture.google.com/exhibit/travels-of-xuanzang-629-645-ce/nQJS3GyICUOmKg. The main map from that site is presented below; opening it in a new tab, you should be able to zoom in and examine it in detail.
[1] Other early travelers, some much earlier, are listed here. While we did not explore all of these, in general, the travelers explored in our project were those whose records were available to us in English translation.
[2] Sramana Huili and Shi Yancong, eds.; Li Rongxi, trans., A Biography of the Tripitaka Master of the Great Ci'en Monastery of the Great Tang Dynasty. Numata Center fo Buddhist Translation and Research, 2006. An older (1911) translation is freely available online at https://hdl.handle.net/2027/hvd.32044009550468.