TEA HORSE ROAD , China , Tibet , Trade and Transport , Commerce , Tea , Caravan , Sipsongpanna , Xishuangbanna , Pu'er , Dali , Lijiang , Kham , Khampa , Yak , Muslim , Islam , Buddhism , Religion , Nathu La , Joseph Rock , Lhasa , Silk Road , Butter Tea , Horse , Mule , Ya'an , Kangding , Sikkim , Darjeeling , Burma Road , Ledo Road , The Hump , China Burma India Theatre