Wat Sing Sai was located on the city island in the southwestern area of Ayutthaya in the Pratu Chai Sub-district. It was situated in the Somdet Phra Sri Nakharin Park, part of the Ayutthaya Historical Park. The site of the former monastery is accessible via U-Thong Road.
The monastery belonged to a cluster of temples located along a canal connecting Wat Luang Chi Krut with Wat Jao Prap, running parallel with the city’s defence wall. Wat Sing Sai stood in between Wat Luang Chi Krut and Wat Nok.
This cluster of temples was located in a residential area in the reign of King Chakkraphat (1548-1569 CE), also called the Lord of the White Elephants. Thianracha had his princely residence in the area before ascending the throne. The location was important, as most of the palace officials and high ranked persons were living on both sides of the Lopburi River between Wat Phutthaisawan and Wat Chai Watthanaram.
The last traces above the ground level of this temple probably disappeared when the Somdet Phra Sri Nakarin Park was constructed. Only a large grass field remains.
Its historical background and the exact construction period are unknown, although it is very likely that the former monastery was built in the middle Ayutthaya period (1488 - 1629 CE).
The site shows on Phraya Boran Ratchathanin’s map drafted in 1926 CE and on the Fine Arts Department (FAD) maps from 1974 and 1993 CE. The temple disappeared from the 2007 CE GIS FAD map for a reason unknown.
Wat Sing Sai must have been approximately located in geographical coordinates: 14° 20' 29.78" N, 100° 33' 5.45" E.