U Thong (, ) is the district (amphoe) in the western part of Suphan Buri province, north of Bangkok.
Higham states, "U-Thong was occupied for many centuries prior to the development of the Dvaravati state. Radiocarbon determinations from the sites of U-Thong and Chansen suggest that the transition into complex state societies in the Chao Phraya basin took place between about 300âÂÂ600 AD." A copper inscription from the mid-7th century states, "Sri Harshavarman, grandson of Ishanavarman, having expanded his sphere of glory, obtained the lion throne through regular succession," and mentions gifts to a linga. The site includes a moat, 1,690 by 840 m, and the Pra Paton caitya.
It also became the origin of the Ayutthaya Kingdom, as the first King of Ayutthaya, Ramathibodi, was prince of U Thong when the city was struck by an epidemic, prompting him to relocate east and found Ayutthaya.
U Thong district was created with the name Chorakhe Sam Phan in 1905. In 1939 the district was renamed U Thong. In 1944, the government moved the centre of the district from Ban Chorakhe Sam Phan to the area of the ancient city.
Neighbouring districts are (from the north clockwise): Don Chedi, Mueang Suphan Buri, Bang Pla Ma, Song Phi Nong of Suphan Buri Province; Lao Khwan, Huai Krachao, and Phanom Thuan of Kanchanaburi province.
U Thong district is divided into 13 sub-districts (tambons), which are further subdivided into 154 administrative villages (mubans).
There are nine sub-district municipalities (thesaban tambons) in the district:
There are six sub-district administrative organizations (SAO) in the district: