Phimai Historical Park is situated at Tambol Nai Muang, Phimai District 60 km northeast of the city of Nakhon Ratchasima Province.
It is the site of Prasat Hin Phimai, one of the most important Mahayana Buddhist temple in Thailand, dating to about 1000 years ago. Prasat Hin Phimai is one of the biggest and most important religious sanctuaries found in Thailand.
It was build around the 11th – 12th century A.D. and additions were made during the 13th century A.D. The ancient city of Phimai is located in the current Phimai town. The old town walls measure 565 by 1,030 m and are rectangular in shape.
These are surrounded by a moat with the Mun River on the north and east sides, the Khem Stream on the south and the Chakarat River on the west flowing to meet the Mun River.