The 2013 excavation campaign of the Mission Franco-Khmère pour l’Aménagement du Territoire Angkorien (MAFKATA) led to the discovery of a unique temple in the dike of the Western Baray, Prasat Ta Poy Chap. The campaign, this year, aimed at deepening our knowledge of pre-Angkorian sites of the Ak Yum region. A GPR campaign conducted in early January 2013 confirmed the existence of a channel at the base of Ak Yum dam and architectural structures at Tuol Ta Trao. But the GPR was ineffective in addressing the organization of domestic installations on Ak Yum southern mounts, and guiding the initially programmed excavations. We have, hence, reconsidered the opportunity to expand the 2012 excavations. Taking  full advantage of the new LiDAR topographic data, a series of surveys was conducted in the area to check the status of the sites and their accessibility. The unknown site of Prasat Poy Ta Chap CP634 was chosen for the 2013 excavation campaign. Located near the southwest corner of Western Baray on the outer shore , the site of Prasat Poy Ta Chap was discovered in 1997 by C. Pottier and some evidence suggested the existence of an ancient institution covered by the dike of the baray, offering a rare opportunity to study the installation and modification of a building before it was sealed by the baray. The excavation was conducted from February 5 to February 20, followed by an analysis period of about a month. The excavations pits were refiled on March 19 and the material study was extended for three months. The research operations have combined mechanical and manual searches, and were limited by the size of the baray dam embankments to the east, and the presence of a high water table in the west. However, three areas of search have enabled us to identify the eastern facade of the disappeared sanctuary and investigate its southern and western sides. Excavations at Poy Ta Chap therefore revealed the presence of an important unknown sanctuary, probably erected between the late 8th and the first half of the 9th century. He remained active during the first phase of construction of the West Baray during the first half of the 11th century. Enhancement and expansion of this dam led to the complete destruction of the sanctuary while a canal was built at the foot of dam, but no activity seems to have taken place on the baray dikes. Ta Chap Poy presents us with a unique  case of foundation posterior to the foundation of Ak Yum, and may reflect the activity of King Jayavarman III in this region.

 excavations