Not far outside the royal city of Angkor Thom is the large monastic complex of Preah Khan. Like Ta Prom, this temple is still mostly in the embrace of the jungle with many collapsed sections, but it is in the process of being stabilized, although the decision has been made not to fully restore it.
Preah Khan was built around 1191 by the great King Jayavarman VII. The temple is part of a group that includes the Neak Pean and Ta Som temples. Like many temples built by Jayavarman VII, Preah Khan was originally built as a Buddhist monastery, but Buddhist images were removed or altered and Hindu elements were added in the centuries after the King's death.
Preah Khan was dedicated to Jayavarman's father. The name means 'sacred sword', a possible reference to a weapon supposedly handed down to successive Khmer rulers from Jayavarman II. One theory suggests that the sword was housed in this monastery. One of the most unique features of the temple is a two story building north of the large courtyard just inside the main eastern entrance. The columns of the first story of the building are round, the only examples of round columns at Angkor. Next to this building is a high open terrace. Some think it may have been used for ceremonies using the sacred sword, which was stored in the special two story building. Today, the terrace makes a good place to get a good view of the inner sanctuary.
The inner sanctuary is very large, and all on one level. With many collapsed roofs blocking passages, it's quite a maze. Beneath the domed roof of the central sanctuary is a stone stupa (chedi) that was added in the sixteenth century. The galleries around the main sanctuary are definitely worth exploring. There are several bas-relief sculptures of interest.
Most people enter and leave Preah Khan by the west entrance, although entering by the east would give you a better impression of the full grandeur of the design.