Wat San Jao Thung, or the Monastery of the Shrine of the Field Spirit, was located on Ayutthaya's city island outside the Historical Park in the Pratu Chai Sub-district.
There are no traces anymore visible of the monastery above ground level.
Historical data about the monastery and its construction are unknown.
Wat San Jao Thung on the maps:
A 19th-century map by an unknown surveyor shows Wat San Jao Thung between the Pratu Thep Mi Canal (1) and the Chakrai Noi Canal (2), but closer to the latter, north of the old road linking the Nang Hong Bridge, Lion Bridge, Wanon Bridge and Chikun Bridge, today defunct. Wat Kot (Wat Borom Phuttharam) stood south opposite the road mentioned above, Wat Jingjok east, an unidentified monastic structure north and Wat Dawadung northeast. The map does not show the existence of a stupa.
The location on the 19th-century map does not match with Phraya Boran Rachathanin's (PBR) map drafted in 1926 CE, which indicates this temple on the west bank of Khlong Chakrai Noi and south of Talaeng Kaeng Road (3). Wat Pa Nai was northeast, San Phra Kan northwest, and Wat Pa Phai west. PBR names the site Wat San Jao Thong or the Monastery of the Shrine of the Flag Spirit.
The location on the 19th-century map seems to coincide with Wat Phra Ngam on PBR’s map. Although named a monastery, the site could have been a Chinese shrine.
Wat Sala Jao Thung must have been located in approximative geographical coordinates: 14° 20' 55.92" N, 100° 33' 40.12" E.
Footnotes:
(1) Khlong Pratu Thep Mi was situated on Ayutthaya's city island outside the Historical Park in Pratu Chai sub-district. The north-south running canal had its mouth at the old Lopburi River opposite the mouth of Khlong Phraya Phan, leading to Wat Phraya Kong and Wat Phraya Phan. The canal was fed by the waters of Bueng Phra Ram, which in its turn was filled by the waters of the Lopburi River via the Lam Khu Pak Sra. The canal passed the fortified city wall at the Thep Mi Gate, also known as the Khao Semi Gate, a large watergate. The canal has been filled up after the fall of Ayutthaya (1767 CE), and only a few traces of the waterway are left today.
(2) Khlong Chakrai Noi is a defunct canal of which some small stretches remain on the premises of the Rajaphat Institute, south of Rojana Road. The premises of the Sam Chao Phraya Museum also show a stretch of water, but here the old canal has been probably altered. Khlong Chakrai Noi had its mouth in the loop of the old Lopburi River around the city, a stretch that became the Chao Phraya River in the 19th century due to deviation works.
(3) Talaeng Kaeng (gallows) was a crossroad close to the city's centre, also used as an execution ground. Currently, it is (more or less) at the junction of Pa Thon and Si Sanphet roads.
