<正>The trade between Yunnan and Tibet has continued for a long time.In modern Shangri-La,there is an ancient town called Dukezong.In Chinese historical literature,it is recorded as East Iron Bridge Town.Dukezong is an important place for YunnanTibet trade.Yunnan is the home of tea and Tibetans have long had the habit of drinking tea everyday.Yunnan is situated adjacent to Tibet;