Wat Kao, or the Old Monastery, was situated on the city island in the southwestern area of Ayutthaya in the Pratu Chai Sub-district and the Ayutthaya Historical Park. The temple was located on the west bank of Khlong Chakrai Yai (1). Wat Khun Phrom (defunct) stood in the north, while Wat Pi Rai (defunct) was in the south. Opposite Khlong Chakrai Yai stood Wat Rak (defunct).

The ancient site was cleared in the early 1970s during construction works of an expansion project of the (former) Ayutthaya Agriculture School (Withayalai Kasetrakam). There are no traces of foundations or brickwork at ground level, and I classified the temple as defunct. [1]

The site is mentioned on Phraya Boran Rachathanin's map drafted in 1926 CE and the 1974 and 1993 CE Fine Arts Department maps. Phraya Boran (1871-1936 CE) was the Superintendent Commissioner of Monthon Ayutthaya from 1925 till 1929 CE. Historical data about the monastery and its construction is unknown.

The site should have been approximately in geographical coordinates: 14° 20' 55.78" N, 100° 33' 20.67" E.


(1) Khlong Chakrai Yai is part of a waterway running through the west of Ayutthaya from north to south. The canal was the extension of Khlong Pak Tho and ran from the Lam Hoei Bridge to the Chakrai Yai Gate opposite Wat Phutthaisawan. The canal was a shortcut through the oxbow of the Lopburi River and connected the old Lopburi River, present Khlong Mueang in the north with - what is today - the Chao Phraya River in the south. Ban Chakrai was a village located on the city island but outside the city walls.


[1] Bangkok Post - 9 Dec 1972 - Work suspended on Ayutthaya sites. The article states that "machinery engaged on the Ayutthaya Agriculture School extensions ploughed up the ruins of at least five temples in the disputed area". The work at the school was stopped after students had sent a petition to the NEC. The Director-General of the Fine Arts Department at that time stated he was certain the damage had already been done.