#11: The Tomb of Qin Shi Huang, China
The Terracotta Army is world-famous, but the emperor’s main burial chamber remains unexcavated. Ancient accounts describe rivers of mercury, traps, and a miniature underground empire, and modern studies have found unusually high mercury levels around the tomb mound. Preservation concerns are also central: opening the chamber could destroy fragile materials that have survived for more than 2,000 years. The result is one of archaeology’s great locked doors. China’s first emperor still keeps his final room.
