401 Cavern Heaven, also known as the 401 Command Project, is located at the foot of Zhuzhishan between Xiling Village and Banping Village in Zhangshui Town, Yinzhou District, approximately 50 kilometers away from the urban area of Ningbo. The 401 Project was a military defense tunnel constructed in the 1960s and 1970s as a war preparedness facility.

The 401 Cavern Heaven stretches over 1 kilometer with several exits both to the north and south, situated above the road on the southern slope of the main general mountain. The main exit of the cavern is located on the north slope of the main general mountain, along the road and on the south bank of the stream. Inside, the space is intricately distributed with various uses, winding paths leading to secluded and mysterious depths.






