In desperate circumstances people are often driven to perform feats of mythical proportions. In the late 1100s the medieval kingdom of Georgia was resisting the onslaught of the Mongol hordes, the most devastating force Europe had ever seen. Queen Tamar ordered the construction of this underground sanctuary in 1185, and the digging began, carving into the side of the Erusheli mountain, located in the south of the country near the town of Aspindza. When completed this underground fortress extended 13 levels and contained 6000 apartments, a throne room and a large church with an external bell tower. It is assumed...