Although the Tea Horse Road sounds to our modern ears like a solid entity, it was in fact a complex network of trails that evolved organically. Nothing was planned or laid out. The focal points were the major staging posts on which the trails had to coalesce, beginning with the town of Pu’er, which was the collecting point for the tea being delivered fresh from the tea mountains of Xishuangbanna on either side of the Mekong River in the far south of Yunnan. Other major staging posts were Weishan, Dali, Shaxi, Lijiang, Gyalthang (modern-day Shangri-La, Deqin and Mangkham, each either on a strategic site or in the centre of prosperous farmland. Some stretches of the Road were indeed a single route, often paved with stone, but others were a web of individual trails, particularly over the mountains, where individual muleteers chose their own preferred paths up hillsides. Over recent years, the many parts of the old Tea Horse Road have been assembled like a jigsaw puzzle until we now have at least the broad strokes laid out by mapmakers. To fly between the major towns from the southern tea mountains to Lhasa covers 2,000 km, as you can see in our fly-through movie above, but the full extent of the entire road, taking in the twists and turns and braided web of trails can probably never be calculated, though 4,000 km would not be far from the mark.