1150 CE - The Khmer established the frontier outpost of Sukhothai Ca 1150 CE. [Reference: Wyatt, David K. (2003) - Thailand, A short history (2nd Ed.) - Silkworm Books - page 43]

Situated adjacent to a reservoir named Tra Kuan in the west and the town gate in the north, this ancient monument was known as Theparak Yai Shrine and Ta Pha Daeng Shrine. The oldest surviving Khmer building at Sukhothai, this single sanctuary tower stands on an exceptionally high base adorned with lotus moulding, which gives it imposing proportions, despite not being particularly large. It was built entirely in laterite, although the superstructure has long since collapsed. There are no traces of the original stucco moulding on the building. Projecting chambers were constructed on the east and west sides of the shrine, with the eastern room longer than the western one. During the excavation of the Ta Pha Daeng Shrine undertaken by the Fine Arts Department, the torsos of five life-size statues were uncovered here. They led Boisselier to date San Ta Pha Daeng to the Angkor Wat period during the reign of Suriyavarman II (1113 - 1150 CE). Still, the fragments and the site are generally regarded as from the Bayon period (13th century CE). The objects are exhibited in the Ramkhamhaeng National Museum.