ABSTRACT
The ancient underground rock structures at Longyou were discovered by local residents in 1992, and have been inscribed on the list of Cultural Relics Protection Unit of Zhejiang Province (China). There are no records in the history to describe the application or construction time of this excavation cluster, but two incomplete pieces of glazed pottery, found in one of the caverns, have been dated as from the Xihan dynasty, some 2,000 years ago (Guo et al. 2005). At present, five of the caverns, which are labeled as Nos. 1 to 5, have been explored for tourism (Fig. 1). Many tourists and researchers are attracted by the grand scale of the caverns’ structure, the exquisite chisel marks on the cavity walls and also the confusing building purpose of the underground complex (Yang et al. 2000, Sun et al. 2001, Wang et al. 2006, Zhu et al. 2008).
