Wat Sam Pratu, or the Monastery of the Three Doors, is located off the city island in the northern area of Ayutthaya, in the Wat Tum Sub-district, east of Road # 347. Wat Sam Pratu stood west of Wat Tum and southwest of Wat Hong.

The temple was situated within a loop of the old Lopburi River, of which the southern part is called Khlong Wat Tum and stood on its east bank adjacent to Wat Long Thong. Likely in the reign of King Narai (1656-1688 CE), the loop had been cut straight near Wat Tha Yak and the northern tax station towards Wat Klang Raman. The shortcut canal was called Khlong Bang Khuat, referring to the village Ban Bang Khuat in which location the canal was dug.

In situ are the remains of some walls of a monastic structure, ordination hall or vihara. As it lies behind private property, it is difficult to access. In the same area, there is also a mound with a small wooden deteriorated ghost house.

Its historical background and period of construction are unknown.

The monastery shows on a Krung Kao map of 1916 CE and Fine Arts Department maps since 1993 CE.

The ruin of the monastery is in geographical coordinates: 14° 23' 43.80" N, 100° 31' 48.85" E.