《史记·七十列传·刘敬叔孙通列传》
汉孝惠帝要到东边的长乐宫去朝拜吕太后，还常有小的谒见，每次出行都要开路清道，禁止通行很是烦扰别人，于是就修建了阁道，正好建在未央宫武库的南面。
孝惠帝为东朝长乐宫，及间往，数跸烦人，乃作衤复道，方筑武库南。
Emperor Xiaohui of Han wanted to visit Empress Dowager Lu in Chang Le Palace in the east, and often met with young people. Every time he went out, he had to clear the road, which was very annoying. So he built a terrace, which was built directly On the south side of the arsenal in Weiyang Palace.