Le You Yuan and Lake Qu Jiang are two of the most famous place of Chang An, the Capital of Tang Dynasty, in the old days. There were numerous poems sited these two places, however, their precise location were unknown. Many ancient articles assumed Le You Yuan is at Plan Sheng-Ping, but it contradicts many statements in Tang poems. This study exam the numerous tales on the description of the locations, using archeology techniques together with modern GPS and GIS equipment, discovered that the Le You Yuan is actually in the highland of Plan Xiu-Zheng instead of Plan Sheng-Ping.