Mapping old communication routes is of crucial importance to understand the history of Kham region prior to mid-20th century as today’s motor roads do not follow precisely traditional caravan and trade routes. In order to find out old routes we can rely on different kind of documents: Tibetan biographies and pilgrimage diaries of religious figures (place names, passes they used to cross, etc.); Chinese sources (for example Weizang tushi maps and accounts); Travel accounts and maps of Western travelers and missionaries from mid-19th to mid-20th century.