Why don't Hangzhou Qibao, Babao and Jiubao enter in turn?

In the evolution of history, the order was disrupted.

All the castles were built in the Qing Dynasty, and some castles may be damaged or abandoned after so many years. It gradually disappeared.

In order to facilitate tidal observation and flood control, the flood control battalion built castles and houses near the jurisdiction to rest and store tools. Fort houses are relatively simple, and some are like thatched houses where farmers live.