Angkor Thom is a gigantic fortified city built around the model of the Hindu Mt Meru surrounded by the oceans. The main temple is called Bayon. All the information in quotes is from Lonely Planet’s Cambodia guide.
“Unique even among its cherished contemporaries, Bayon epitomises the creative genius and inflated ego of Cambodia’s legendary king Jayavarman VII. …locals suggest that the Khmer empire was divided into 54 provinces at the time of Bayon’s construction, hence the all-seeing eyes of Avalokiteshvara (or Jayavarman VII) were keeping watch on the kingdom’s outlying subjects.”