What was the last capital city of the Khmer Empire in Cambodia?

Angkor Thom located in present-day Cambodia, was the last and most enduring capital city of the Khmer Empire. It was established in the late twelfth century by King Jayavarman VII. It covers an area of 9 km², within which are located several monuments from earlier eras as well as those established by Jayavarman and his successors. At the centre of the city is Jayavarman's state temple, the Bayon, with the other major sites clustered around the Victory Square immediately to the north. The site is one of the major tourist attractions of Southeast Asia.

The Khmer Empire was a Hindu-Buddhist empire in Southeast Asia, centered around hydraulic cities in what is now northern Cambodia. Known as Kambuja by its inhabitants, it grew out of the former civilisation of Chenla and lasted from 802 to 1431. Historians call this period of Cambodian history the Angkor period, after the empire's most well-known capital, Angkor. The Khmer Empire ruled or vassalised most of mainland Southeast Asia and stretched as far north as southern China. At its peak, the Empire was larger than the Byzantine Empire, which existed around the same time.