4. Tomb of Qin Shihuangdi
Chinese farmers unearthed the fabled terracotta army of Emperor Qin Shihuangdi in 1947. The emperor was supposed to be protected by the sculptures in the afterlife. His interment space and belongings, however, are still a mystery. It’s thought that the emperor’s tomb is a subterranean palace that deceives the tomb raiders into thinking it’s miles away from the army. It is hard, if not impossible, to find, therefore the mystery stays unresolved.