Wat Saphan Kluea on the maps
The monastery is indicated on a 19th-century map in front of Wat Khwang Fortress on the opposite side of the city island and near the confluence of the Front Moat and the former Khlong Sai (4).
Wat Saphan Kluea is also mentioned on Phraya Boran Rachathanin's [PBR] map drafted in 1926 CE. PBR seems to indicate two structures. The structure in the west is Wat Saphan Kluea, but the structure in the east is marked on a 1993 CE FAD map as Wat Jampa (5), a different temple. Wat Saphan Kluea has been shown on all Fine Arts Department maps since 1957 CE.
Wat Saphan Kluea was one of the six monasteries on Ko Loi. The other temples were Wat Monthop, Wat Khae, Wat Inthawat/Wat Sri Jampa, Wat Ngu and Wat Khao San Dam.
The remaining brickwork of Wat Saphan Kluea is in geographical coordinates: 14° 21' 57.72", N 100° 34' 41.28" E.
Footnotes:
(1) Ko Loi, or Floating Island, is surrounded in the north by Khlong Chong Lom, in the east by the (new) Pa Sak River and in the west by the (new) Lopburi River. Khlong Chong Lom was dug in the early 20th century to reduce the whirlpools near Wat Tong Pu and the Chantra Kasem Palace, separating Wat Chong Lom from the eastern mainland. As the Lopburi River and the Pa Sak River were joining near Wat Tong Pu, and the erosive force of the two rivers was destroying the embankment in front of the Chantra Kasem Palace, the idea rose to divert the Pa Sak River. The diversion was made shortly after the digging of Khlong Chong Lom. Khlong Sai, a small canal cutting through the eastern mainland from Wat Chong Lom to the present Ayutthaya Ship Building Industrial and Technology College, was widened and deepened. The Pa Sak River, instead of running in front of Wat Tong Pu, changed its course and ran straight from Wat Pa Kho to Wat Phanan Choeng.
(2) Khlong Na Mueang, or Khu Khue Na (Front Moat), ran east of the city of Ayutthaya. The former moat is said to have been dug in the reign of King Ramathibodhi I, also called King U-Thong. It was initially a defensive moat or could have been a separation ditch (borderline) between the ancient city of Ayodhya, situated in the oxbow of the Pa Sak River and the newly established city of Ayutthaya in the oxbow of the Lopburi River. The Royal Palace stood on the premises of the present ruins of Wat Phra Si Sanphet, and the earthen walls surrounding the city were likely not further than the moat, later known as Khlong Pratu Khao Pluak.
(3) In the Ayutthaya era, there were twenty-two ferry routes. In the eastern area, the four other crossings were: Tha Chang Wang Na to Tha Wilanda, south of Wat Khwang to Wat Nang Chi, south of Wat Pa Thon to Wat Phichai and north of Rachakrue Fortress to Wat Ko Kaeo. [1]
(4) Khlong Sai is a defunct canal once situated off the city island in the northern area, in the Hua Ro Sub-district and, at present, a stretch of the Pa Sak River. Khlong Sai, or Sand Canal, was a small canal cutting through the eastern mainland, in front of Wat Khae and Wat Chong Lom, going south towards the present Ayutthaya Ship Building Industrial and Technology College, where it joined the Front Moat or Khu Khue Na.
(5) On a 2007 FAD GIS map, this structure is called Wat Inthawat (Wat Sri Jampa).
References:
[1] Baker, Chris (2011). Before Ayutthaya Fell: Economic Life in an Industrious Society. Markets and Production in the City of Ayutthaya before 1767: Translation and Analysis of Part of the Description of Ayutthaya. Journal of the Siam Society. Vol. 99.
[2] Loubère, Simon (de la) (1691). Description du Royaume de Siam (2 Tomes). Amsterdam.
[3] Baker, Chris & Phongpaichit, Pasuk (2017). A history of Ayutthaya, Siam in the Early modern World. Cambridge University Press.
[4] Cushman, Richard D. & Wyatt, David K. (2006). The Royal Chronicles of Ayutthaya. Bangkok: The Siam Society. pp. 64-5.
[5] Rachathanin, Phraya Boran. Athibai Phaenthi Phra Nakhon Sri Ayutthaya kap khamwinitjai khong Phraya Boran Rachathanin. Explanation of the map of the Capital of Ayutthaya with a ruling of Phraya Boran Rachathanin - Revised 2nd edition and Geography of the Ayutthaya Kingdom. Ton Chabab print office. Nonthaburi (2007).
[6] Baker, Chris (2014). Final Part of the Description of Ayutthaya with Remarks on Defense, Policing, Infrastructure, and Sacred Sites. Journal of the Siam Society, Vol. 102.
[7] Baker, Chris (2011). Before Ayutthaya Fell: Economic Life in an Industrious Society. Markets and Production in the City of Ayutthaya before 1767: Translation and Analysis of Part of the Description of Ayutthaya. Journal of the Siam Society. Vol. 99.