Angkor Thom is not a singular temple dedicated to a Hindu deity such as Angkor Wat; instead, it is the name of one of the most impressive royal cities of the Angkor Period (9th–15th centuries) and an urban planning marvel. At the height of its power, the Angkor Empire (also called the Khmer Empire) controlled much of modern day mainland Southeast Asia. However, the center of its kingdom always remained in Angkor, in what is today Siem Reap city.
The Angkor Thom is the central part of the Angkor city, which covers a square area of 9 km2, and is surrounded by a moat and a 8 m tall wall.
A prominent feature is the huge faces of a human head on all four sides of tall towers.