Wat Tha Sai, or the Monastery of the Sand Landing, is a restored ruin situated on Ayutthaya’s city island in the Tha Wasukri Sub-district. The restored ruin is located along U Thong Road on the premises of Wat Racha Praditsathan, as it is today considered part of the premises of the latter.

Wat Tha Sai was located next to the mouth of Khlong Pratu Khao Pluak, which once separated it from Wat Racha Praditsathan (on the opposite side of the canal). This canal has been filled in, for the most part, leaving a small pond on the premises. Traces of the Pratu Khao Pluak fortress and the watergate Pratu Khao Pluak still can be seen in situ. Khlong Pratu Khao Pluak, or the ‘Canal of the Gate of Unmilled Rice’, was part of a waterway running through the middle of Ayutthaya from north to south. The canal, a shortcut in the oxbow of the Lopburi River, ran until the Chikun Bridge and continued to the Chinese water gate (Pratu Jin).


A renovated open-air shrine stands in the location of the original vihara, containing several rows of beautiful, white-painted, mediating Buddha images. The earlier makeshift tin roof collapsed due to a significant storm in July 2009. In front of the main Buddha image sit Buddha’s two chief disciples, Moggallana and Sariputta, surrounded by smaller buddha statues aligned left and right of the main image.

To the west of the shrine stands the central stupa. Though it is difficult to discern, the upper part of the stupa looks like a prang. The drum is octagonal with multiple arched niches holding standing Buddha images and has the entry to the east. Minor chedis surround the stupa.

The ordination hall was seriously dilapidated but was renovated after the great flood of 2011. The hall had its main entry in the east, and on the west side of the building was a shelter with a reclining Buddha. The ubosot was surrounded by single plate boundary stones.

A second building stands behind it. Although worn and covered in graffiti, inside the second structure, there are the remains of several Buddha images within arched niches.

The site also has a bell tower on a square base with niches, several bell-shaped chedis and dozens of memorial monuments (with a surprisingly large amount of Chinese headstones). A large modern mandapa covered in brown tiles stands out on the premises, but this is usually closed to public viewing.


Wat Tha Sai is mentioned in the Royal Chronicles of Ayutthaya. King Prasat Thong (reign 1629-1656 CE) was celebrating Khao Phansa at Wat Phra Si Sanphet, circumambulating the main vihara when he saw the youngest son of King Songtham (reign 1610/1611-1628) sitting on the inner wall, observing the procession, not paying his respects to the king. The ten-year-old Prince Athittayawong was made king of Ayutthaya in 1629 CE, after the execution of his older brother, King Chettha (reign 1628-1629 CE), but due to his childhood dethroned by the Kalahom, the Minister of Defense after five weeks. The latter, the new King Prasat Thong, got him punished by stripping of his rank and sending him out of the Grand Palace area in exile near Wat Tha Sai. To be correct, I need to mention that it could also have been possible Wat Tha Sai in the Khlong Khu Cham area, an area often used to exile prominent persons during the Ayutthaya era.

When it was the beginning of the monsoon season in the eighth lunar month, the Supreme-Holy-Lord-Omnipotent proceeded forth with His concubines and beautiful royal ladies to venerate and light monsoon season candles to the statue of the Buddha at the Monastery of the Holy and Glorious Omniscient One. His Majesty came on a tour in front of the large holy preaching hall and, glancing with His holy eyes, saw Holy Athittayawong, the royal son of Holy-Lord Song Tham who had been removed from the royal wealth, ascend and sit dangling his feet upon the back of the crystal wall. Indicating him with His holy hand the King said, “Athittayawong is rash in failing to descend from the crystal wall in order to be lower than the King. Strip Holy Athittayawong of his rank and send someone to build two houses with bamboo posts and two rooms beside the Monastery of Sand Landing for Athittayawong to Have two people live with him - just enough to dip up water and cook rice.” After the order His Majesty entered the holy royal palace. [1]

During the Burmese attack on Ayutthaya, a large fire broke out at the end of 1766 CE in the vicinity of Wat Tha Sai. The fire, likely supported by the northern wind of the cool season, raged until Thon Market and Wat Chatthan. Ten thousand structures, being temples and houses, were burned during that night.

When it was the first month of the year of the dog, eighth of the decade, in the evening, a fire broke out at Sand Landing, burned and spread in to the Bridge of the Elephants, and came across and ignited the Coconut Forest, the Thon Forest, the Charcoal Forest, the Flame Tree Forest, the Grass Forest, all the way to the Monastery of the Royal Repairs and the Monastery of the Holy Grand Reliquary. The fire continued and stopped only at the Monastery of Chatthan. [2]

Near Wat Tha Sai was one of the seven ferry landings on the northern side (five regular ferries and two official ferries) connecting to Wat Rong Khong (today named Wat Wong Khong) on the other side of the old Lopburi River (today the City Canal). Close to the landing and on the western bank of the canal, still on the south bank of the old Lopburi River, stands a brick chedi indicating the former entry of the canal. [2]

At Tha Sai, shops were selling sompak cloth (1), cloth with phum silk borders, Gujarat patterned cloths, yammawat lower-cloths (2), bordered sompak, striped sompak, and prostration cloths, big and small. When officials had no time to fetch a cloth to change, they had to buy here to enter in audience. [3]

Wat Tha Sai on the maps

Wat Tha Sai shows on Kaempfer’s sketch. Engelbert Kaempfer (1651-1716 CE) was a medical doctor working for the Dutch VOC (Verenigde Oost-Indische Compagnie) who surveyed the city of Ayutthaya in June 1690 CE. The temple is situated on the east bank of Khlong Pratu Khao Pluak, close to the northern city wall. We can see a chedi opposite Wat Racha Praditsathan. There was a road running north, from Elephant Road near the Elephant Bridge towards the northern city wall and Wat Tha Sai. On this road, we can discern a bridge over the Ho Rattanachai Canal, which connects with Khlong Pratu Khao Pluak.

The monastery does not appear on Bellin’s map, ‘Plan De La Ville De Siam’, although the two bastions along the Khao Pluak canal can be seen. Jacques-Nicolas Bellin (1703-1772 CE) was one of the most important cartographers of the 18th century.

Wat Tha Sai is indicated on a map drafted in the 19th century by an unknown surveyor. The monastery stands at the eastern bank of Khlong Pratu Khao Pluak near the confluence with the old Lopburi River. Wat Pra (Wat Racha Pradisathan) sits on the opposite bank, while Wat Khian stands further east. The map shows the presence of a prang. The boat landing is indicated.

The temple is on Phraya Boran Rachathanin's map of 1926 CE in an identical position as the 19th-century map. Phraya Boran (1871-1936 CE) was the Superintendent Commissioner of Monthon Ayutthaya from 1925 till 1929 CE.

The Fine Arts Department [FAD] drafted in 1957 and found in the ‘Guide to Ayudhya and Bang-Pa-In,’ shows ‘Wat Ta-Sai'.

The ruins of Wat Tha Sai are in geographical coordinates: 14° 21' 47.27" N, 100° 34' 8.57" E.


(1) A form of lower-cloth especially for nobles attending audience, generally made by seaming two narrow strips together resulting in cloth much larger than usual, around 160 centimetres wide, and requiring a special and more elaborate form of wearing with a pattern showing on both ends. [2]

(2) A printed cotton from Ahmedabad. There are several explanations of the origin of the name, including a distortion of Ahmedabad, a Persian word for wool fabric, and an old Thai term for purple dye. [2]


[1] Cushman, Richard D. & Wyatt, David K. (2006). The Royal Chronicles of Ayutthaya. Bangkok: The Siam Society. p. 217 / Source: Phan Canthanumat, British Museum, Reverend Phonnarat, Phra Cakkraphatdiphong & Royal Autograph - King Prasat Thong, 1629-1636. [2] Cushman, Richard D. & Wyatt, David K. (2006). The Royal Chronicles of Ayutthaya. Bangkok: The Siam Society. p. 514 / Source: Phan Canthanumat, British Museum & Reverend Phonnarat - Phræ Deserts the Burmese Forces.

[2] 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.

[3] 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.