Buried deep near Xi’an, beneath a hill that was built over it and surrounded by an underground ditch filled with poisonous mercury (at that time was thought to give immortality), are the remains of the first Chinese emperor, undisturbed for over two millennia: Qin Shi Huang died on September 10, 210 BC.
The tomb complex is made of underground caves that contain every good that the emperor thought he needed in the afterlife: the most famous part consists of the terracotta army, reproduction of the army that allowed Huang to conquer all of China, discovered by chance in 1974.
The central building containing the body of Qin Shi Huang is still completely closed: from ancient evidence we know that the emperor had an entire underground kingdom built, with the ceiling imitating the night sky with pearls depicting the stars.
The excavations have never been authorized by the Chinese government, as it expects, wisely, to be sure to have at its disposal the necessary technologies so as not to risk damaging the finds. The mercury moat is a further deterrent to archaeological excavations because it is potentially dangerous: in the soil of the hill have been found levels of mercury 8 times higher than the surrounding areas and are still uncertain the consequences in opening the place.