The town of Phimai, 60 kilometers north of Korat, is home of the amazing 900 year old Phimai Historical Park, perhaps the most important Khmer historical site in Thailand.
The Khmer existed from the early 9th century until 1431, when they were overthrown by the Thais. Its base was in Angkor, in present-day Cambodia and stretched to parts of what is now Thailand. The most famous of all Khmer sites, Angkor Wat (opens in new window), in Angkor, was the capital.
It is believed that Phimai Historical Park was built before Angkor Wat and may have acted as a model. It's thought the 2 sites used to be connected by a road lined with hundreds of stone temples!