Preah Khan or NAGARA JAYASRI
Preah Khan was built on the site of Jayavarman VII's victory over the invading Chams in 1191. Unusually the modern name, meaning "holy sword", is derived from the meaning of the original—Nagara Jayasri (holy city of victory). The site may previously have been occupied by the royal palaces of Yasovarman II and Tribhuvanadityavarman. The temple's foundation stela has provided considerable information about the history and administration of the site: the main image, of the bodhisattva Avalokiteśvara in the form of the king's father, was dedicated in 1191 (the king's mother had earlier been commemorated in the same way at Ta Prohm). 430 other deities also had shrines on the site, each of which received an allotment of food, clothing, perfume and even mosquito nets; the temple's wealth included gold, silver, gems, 112,300 pearls and a cow with gilded horns. The institution combined the roles of city, temple and Buddhist university: there were 97,840 attendants and servants, including 1000 dancers and 1000 teachers.
The secret place of the greatest king kept his secret weapon (Preah Khan or Sword). who invaded the city make Khmer empire really powerful and combined religion Hindu and Buddhism.