The temple Prasat Hin Phimai, located in the center of the town, was one of the major Khmer temples in ancient Thailand, connected with Angkor by the Ancient Khmer Highway, and oriented to face Angkor as its cardinal direction.

As the enclosed area of 1020x580m is comparable with that of Angkor Wat, it is suggested to have been an important city in the Khmer Empire.

The site was put under Thai governmental protection by announcement in the Government Gazette, Volume 53, section 34, on September 27, 1936.

The historical park, now managed by the Fine Arts Department, was officially opened by Princess Maha Chakri Sirindhorn on April 12, 1989.

Art and architecture shown on the temple itself shows great evidence of the ancient Khmer civilization.

Evidence of Dvaravati influence, such as the sculpture of "the Wheel of Law" or the statue of Buddha, shows that Phimai was an important Buddhist spiritual location.

Phimai, along with other Khmer temples in Thailand, were built mainly under the cause of the "Deveraja cult," or "the King that resembles a god."

Under this principle, Khmer rulers built temples to glorify the reign of the king along with the spread of Hinduism.

Adjacent to this is a collection of statues of devils and animals depicted from the Tantric Mahayana Buddhist scripture.

Located in the middle of Phimai is a small rectangular gallery surrounding the courtyard, which has been newly rebuilt.

The Royal Fine Arts Department also built an inner gallery that shows ancient Buddhist inscriptions and small sculptures as well as pieces of wrecked architecture.

The Khmer did not develop the technique of true vault architecture during their time, resulting in large areas at Phimai that could not be roofed over.

Temple construction during the Angkorian period involved the deliberate deposition of layers of fill, which can clearly be seen in the stratigraphy of the site.