The Bayon was the last state temple to be built at Angkor, and the only Angkorian state temple to be built primarily as a Mahayana Buddhist shrine dedicated to the Buddha, though a great number of minor and local deities were also encompassed as representatives of the various districts and cities of the realm. It was the centrepiece of Jayavarman VII's massive program of monumental construction and public works, which was also responsible for the walls and naga-bridges of Angkor Thom and the temples of Preah Khan, Ta Prohm and Banteay Kdei.

The Bayon's most distinctive feature is the multitude of serene and massive stone faces on the many towers which jut out from the upper terrace and cluster around its central peak. The temple is known also for two impressive sets of bas-reliefs, which present an unusual combination of mythological, historical, and mundane scenes. The main current conservatory body, the JSA, has described the temple as "the most striking expression of the baroque style" of Khmer architecture, as contrasted with the classical style of Angkor Wat.

The similarity of the 216 gigantic faces on the temple's towers to other statues of the king has led many scholars to the conclusion that the faces are representations of Jayavarman VII himself.

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  http://en.wikipedia.org/wiki/Bayon