당 고조
The name Hulao, or "Tiger Cage", came to be when King Mu of Zhou trapped a tiger in this place. It also had the name of Wulao Pass () at one time in the Tang Dynasty, due to a naming taboo — the grandfather of Emperor Gaozu of Tang was named Li Hu. The pass also held the name Sishui Pass () from time to time, which brought much confusion whether Hulao Pass and Sishui Pass are referring to the same pass. Luo Guanzhong, the author of "Romance of the Three Kingdoms", apparently also got confused over the names and treated Sishui Pass and Hulao Pass as two places when they should be one.