Phimai Historical Park is an ancient Khmer city of the Khmer Empire in Thailand situated in Phimai District of Nakhon Ratchasima Province and is about 60 kilometers north from Phimai, the Capital. The ancient Khmer city [ and earlier in 7 - 8 C part of Chenla Kingdom ] is surrounded by a moat adjacent to the Mun River on the east and north boundaries. Phimai is the largest Khmer ruins complex in Thailand and comprises an inner moated city, 565 by 1030 metres, which was built in the 11 – 12 C with further additions in the 13 C.

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