AYUTTHAYA HISTORICAL RESEARCH



THE CITY WALLS OF AYUTTHAYA





Establishing Ayutthaya (1351 CE)


The location of the city of Ayutthaya had been chosen merely for its strategic position in the oxbow of the Lopburi River. The first wall around Ayutthaya, built by King Ramathibodhi I (reign 1350-1369 CE), was merely a moat-and-mound enclosure with wooden stakes driven into the ground on an earthen rampart. The city was surrounded on its northern, western, and southern flanks by the Lopburi River, a natural barrier that was easy to protect. Only the city's eastern side was prone to an easy attack as no natural defence existed. The eastern defences at that time were made up of a large moat and wooden enclosures, stretched only until the middle of today's city island.


The large eastern moat became later known as Khlong Pratu Khao Pluak - Khlong Pratu Jin (1). This canal does not exist anymore, but still, some traces remain of it on the premises of Wat Ratcha Praditsathan.





(A remnant of Khlong Pratu Khao Pluak on the premises of Wat Ratcha Praditsathan – Picture taken October 2024 CE)



Citing the Chronicle of Luang Prasoet, we find two sons of King Intharatcha (reign 1409-1424 CE) fighting for the throne of Ayutthaya in 1448 CE at the death of their father. Ai Phraya, the eldest arriving from Suphan Buri, entered the city first and installed his troops along the eastern moat near Wat Phlapphla Chai, near a bridge, which was likely the sole entry to the settlement. Yi Phraya, arriving from San Buri, took position on the opposite side of the moat near Wat Lat (Wat Chaiyaphum). Both princes seated on elephants fought each other at the foot of that bridge, and both became deadly wounded. Sam Phraya in Chai Nat, being informed of the situation, descended to Ayutthaya and mounted the throne as King Borommaratcha II. In commemorating his two elder brothers, as the legend goes, he ordered the construction of two chedis near the Pa Than Bridge, where the fight occurred. The foundations of these two chedis still can be seen today.


“In 786, a year of the dragon, King Intharacha I became ill and passed away. At that time Prince Ai Phraya and Prince Yi Phraya, young sons of the King, fought each other on elephants at Than Forest Bridge and both of them died there. So a young son of the King, Prince Sam Phraya, ascended the royal throne of the Capital City of Ayutthaya and took the royal title of King Bòromracha II. And he then had two holy monuments built to cover that spot in the Municipality of Than Forest where Prince Ai Phraya and Prince Yi Phraya fought each other to the death on elephants.” [1]





(Chedi Ai and Chedi Yi near the Pathan Bridge – Picture taken October 2024 CE)



First city expansion in the East


Ayutthaya expanded in the eastern direction between 1450 and 1550 CE. A new defensive moat was dug, today known as the Makham Riang Canal, before Khlong Nai Kai. When new moats were dug, the mud and debris were stacked on the bank, the mound serving a defensive purpose and cut down on flooding. This type of defence was used until the mid-16th century. The latter can be deduced from the writings in the Royal Chronicles of Ayutthaya, describing the first fall of the City of Ayutthaya.


The wooden defensive walls were replaced by brick walls (1550 CE)


In 1549 CE, after the first attack on Ayutthaya by the Burmese in the reign of King Maha Chakkraphat (1548-1569 CE), the defences of Ayutthaya were strengthened. Brick walls and fortifications were constructed around the city to replace the old mud banks and palisades used since the city's establishment.


“In 911, a year of the cock, on Saturday, the tenth day of the waxing moon of the second month, a male white elephant was taken in the Municipality of Tenasserim Forest. It stood over four sòk high and was named Patcainakhanet. At that time, the King had the walls of Ayutthaya built for the first time. “ (2) [2]


Prince Damrong wrote that King Chakkraphat realised that Ayutthaya had entered the age of gunpowder, and large guns came to dominate the war theatre and thus strengthened the city's defences by a series of construction works. The construction of forts at the main waterway intersections dates from this period. The city walls were reinforced and redone in brick (brick does not shatter on impact from a cannonball as stone does). A crenellated wall of laterite, brick, and plaster was constructed on wooden beams beneath, serving as foundations and done to stop invading armies from trying to tunnel beneath the defence wall. (3)[3]





(A remnant of the western city wall and embankment along the Chao Phraya River – Picture taken October 2019 CE)



First city expansion in the East


The principal effort of the Burmese attack on Ayutthaya in 1569 CE seems to have occurred in the southeast. The rivers protected the northern, western, and southern flanks of the city as a natural barrier, while the eastern side was easily prone to attack, which occurred here. The troops of Prince Thammaracha from Phitsanulok and the Burmese Uparat (second to the King of Hongsa) advanced over Kaeo Island (loosely translated Crystal Island - the actual location of the temple "Wat Ko Kaeo") towards the city. The enemy took the Siamese stockade at Crystal Island under the command of Phra Maha Thep.


The army of Phra Maha Thep was routed, and he retreated to regroup in the area in front of Kho Monastery and Krabu Monastery. Being routed again and withdrawing to regroup in the vicinage of Phao Khao Monastery, his broken forces were so scattered and repeatedly separated that they could not reform their lines. The enemy, thus, was able to enter the city of Ayutthaya on 30 August 1569 CE, leading to its first fall. The above, related in the Chronicles, indicates that the eastern Ayutthaya city limits in 1569 CE were situated along Khlong Makham Riang (4).


The straightforward Burmese approach of the city makes it clear that the Pa Sak River still ran in its former bed. [4]





(First fall of Ayutthaya – 1569 CE)



Second city expansion in the East (Ca. 1580 CE)


“In 924, a year of the dog, fourth of the decade, the King had the Royal Metropolis renovated. He had the moat by the front ramparts on the east dug ten wa wide and three wa deep from the Maha Chai Fort at the Back Palace down to connect with Kaca Village [Canal?]. Then he had the city walls moved out to the banks of the river, the outer limit of the Royal Metropolis, and connected with the Maha Chai Fort, and from the Maha Chai Fort connected down to the Phet Fort.” [5]


Ayutthaya was conquered for the first time on 30 August 1569 CE and temporarily became a vassal state of Burma. Even under the watchful eyes of the Burmese, King Maha Thammaracha (reign 1569-1590 CE) was allowed to build new walls around the city under the pretext of a threat from Cambodia. (5)[6]


The new walls were extended to the riverbanks in 1580 CE (based on the Chronicle of Luang Prasoet). The moat by the front ramparts on the east - the Khu Khue Na or Front Moat - was dug 20 meters wide and 6 meters deep and extended towards the Mae Nang Pluem Monastery and the mouth of Khlong Khao San. (6)


The Maha Chai Fort was built (7) at the confluence of the Lopburi River and the newly dug shunt connecting the Khu Khue Na or Front Moat to defend the northeastern side of the city. [7]


Likely, Portuguese engineers contributed to the thicker and better-reinforced style of walls. Brick forts were constructed to replace the old fortifications. Known fortresses were Pom Maha Chai, Pom Sattakop, Pom Phet and Pom Ho Ratcha Khrue. Pom Phet’s location at the confluence of the Chao Phraya and Pa Sak Rivers near Hua Sarapha protected the harbour where foreign ships anchored for inspection and unloading. At the same time, Pom Sattakop guarded the north-western part of the city at the confluence of the Maha Phram Canal and the Lopburi River near an area called Hua Laem.





(Remnant of the northern city wall opposite Wat Yan Sen – Picture taken November 2008 CE)



Restoration of the city walls (1634 CE)


The walls of Ayutthaya were restored by King Prasat Thong (reign 1630-1655 CE) in 1634 CE. Jeremias Van Vliet, a merchant of the Dutch East India Company working in Ayutthaya for many years, wrote:


“The town …. is surrounded by a heavy stone wall which has a length of more than two Netherlands miles. This wall was for the greatest part renewed in 1634 and provided with a heavy stone footing.” [8]


Another Dutchman, Jan Janszoon Struys (1630–1694 CE), an explorer whose account of his world travels was published in Amsterdam in 1676 CE, arrived in 1650 CE on the vessel the ‘Black Bear’ in Ayutthaya. He describes the city walls as follows:


“Siam although it have abundance of Towns, yet there are but five that are walled, in all the Kingdom, whereof Iudia is the strongest, being about 3 Dutch miles in circuit: The walls are considerably strong, with round Bulwarks after the old way, but after its manner very Stately and magnificent.” [9]


Since a Portuguese presence dates to the beginning of the 16th century, they likely offered advice and help in the construction of the brick walls and round bulwarks of the city, as mentioned by Struys. The advent of gunpowder and cannons led to the development of round bulwarks, known as bastions, that projected outward from the city walls. The circular was designed to absorb and deflect cannon fire, reducing the likelihood of direct hits that could breach the walls. These round bulwarks were often placed at corners or intervals, allowing defenders to fire in multiple directions and creating a crossfire zone that complicated enemy advances.





(Restored eastern city wall near the Naresuan Bridge – Picture taken May 2015 CE}



Gijsbert Heeck (1619–1669 CE), a ship's surgeon for the Dutch East India Company, stayed in Ayutthaya for two months in 1655 CE. He wrote as follows:


“Concerning this widely renowned royal capital of Siam, named Ayutthaya. It lies on an island completely built up and surrounded with a very high thick wall on all sides. in which are also suitable battlements to run out guns, though at present [They are] without [any], at least as far as we could see. In addition there are proper abutments and buttresses, all built of brick. They have many gates on all sides in order to enter and leave, the city being so populous that there are people living at the foot of the walls on the water.” [10]


Rebuilding of the city walls (1663 CE)


The Sicilian Jesuit and architect who built the San Paolo Church in the old Portuguese enclave, Father Tomaso Valguarnera (1608-1677 CE), was asked by King Narai (reign 1656-1688 CE) in 1663 CE to rebuild the walls of Ayutthaya. He was replaced as superior by Father Cardosa to take care of this task and was occupied with the construction of fortifications until 1670 CE. In 1675 CE, on his return to Siam, we find Fr. Valguarnera again occupied with building the walls of Ayutthaya until he died in 1677 CE. [11]





(The restored northern city wall at Hua Ro – Picture taken October 2024 CE)



Rebuilding of the city walls (1686 CE)


Maintaining these brick walls seemed to have been an ever-ongoing issue, as Nicolas Gervaise wrote around 1686 CE that a new wall was built. The year coincides with the presence of the French self-made 'engineer' (de) la Mare, who was part of the first French Embassy to Siam under de Chaumont and de Choisy in 1685 CE. He remained at King Narai's request to build fortifications. (8)


“The enclosure of the city is only about two leagues, and this includes the royal palace. It is more oval than round and is girt by a brick wall, which is falling into ruin. However, the king is having a new wall built, which is not yet completed.” [12]


Ayutthaya's shift from round bulwarks to angled bulwarks, for example, Pom Phet, originates from the French. The angled bastion design allowed for stronger defensive lines capable of withstanding the artillery advances of the time, and it became the hallmark of French military fortifications under Vauban's influence. Engelbert Kaempfer (1651-1716 CE), a surgeon working for the Dutch East India Company, visited Ayutthaya in 1690 CE. He stayed in Ayutthaya for about a month and made abundant sketches and observations. Kaempfer noted the walls as follows:


“It is surrounded with a Brick wall, which on the South and North is four fathoms and a half high, dean, well condition'd and adorn'd with Battlements, but the rest of it is lower, neglected and decay'd. This wall is open in many places, where there are small gates towards the River. On the inside there are ramparts rais'd against it at different distances for placing Cannons upon them. At the lower end of the City appears a large bastion advancing into the water, besides several small ones. The first is furnish'd with Cannons against the Ships coming up. To fence the City wall against the wasteing of the current, a narrow bank, or key is left, which is built upon in many places.” [13]





(Pom Phet or Diamond Fort – Picture taken July 2012)



A second wall in front of the northern palace wall


In 1760 CE, the Burmese armies invaded Siam. The ex-king Uthumphon (reign 1758 CE), who retired to a monastery, leaving the kingdom to his elder brother, disrobed in 1760 CE on request of the people to take care of the defences of Ayutthaya. He had a second wall built in front of the Grand Palace. The foundations of this second wall rest today under a part of the U-Thong Rd between Wat Thammikarat and Khlong Pak Tho.


“Now the walls of the municipality along the front of the Holy Royal Palace Enclosure on the side toward the edge of the river originally consisted of only a single tier. He had one more tier of walls newly constructed outside and lower than the original walls. And He had teak logs brought up, tied to hang from the boundary stones and pounded into the ground to form barriers to seal off all the water and land gates.” [14]





(The reconstructed northern palace wall, which was also the city wall– Picture taken November 2008 CE)



After the fall of Ayutthaya (1767 CE)


Most parts of the wall and the forts were dismantled in the reign of King Rama I (1782-1809 CE), who had the bricks taken to be used in constructing the city walls for the new capital in Bangkok. [15]


In 1784 CE, bricks from the ruins of Ayutthaya were used to construct a barrage in the Lat Pho Kanal at Phra Pradaeng to halt saline water intrusion farther inland. [16]


Another round of building material gathering occurred in the reign of King Rama III (1824-1851 CE) when remaining bricks and laterite stones, including those of the Thamnop Ro Causeway and the Elephant Bridge, were sent down to Bangkok to be used in the construction of a giant stupa, a copy of Ayutthaya's Chedi Phukhao Thong. Unfortunately, Wat Saket collapsed into rubble. The remains of the crumbled chedi were remodelled in the reigns of Rama IV and V to become known as the "Golden Mount" today.





(The chedi of Wat Saket in Bangkok, former Wat Sakae, before it crumbled and was remodelled)



The remaining foundations of Ayutthaya's city wall disappeared in 1895 CE when the Governor of Ayutthaya, Phraya Chai Wichit Sitthi Satra Maha Pathesathibodi, ordered the construction of U Thong Road, the present road encircling the city island of Ayutthaya. Today, there are only a few - mostly reconstructed - remnants left of the old city wall.


Peter Anthony Thompson was a British diplomat, author, and scholar in the late 19th and early 20th centuries. Thompson served as the British Vice-Consul in Bangkok, which provided him with firsthand exposure to Siamese society, culture, and political affairs during a period of significant modernisation and Western influence in the region. He wrote the following in a visit to Ayutthaya in 1905 CE.


“The remains of the old city wall form an embankment which surrounds the island, and through this our klong cut. Inside we found a clearing in the jungle, where on a sanded space there stood a monastery, shaded by large trees.” [17]


Early 20th-century documents such as Phraya Boran Ratchathanin's ‘Explanation of the map of the Capital of Ayutthaya’ (1929 CE) mention that the walls around the city were built, some with brick, some with laterite, and some with red stone. The wall from ground level to the top of the parapet was 6 meters. Inside the walls, there was a raised earthwork for patrolling inside the walls, 3 meters high and 5 meters wide with passageways. (9) There were forts, camps, moats, and large and small gates around the city. The long side of the city wall was over 4 Km, and the short side was over 2 Km. [18]


Another source writes that archaeological evidence from the Diamond Fort (Pom Phet) indicates that the first walls were up to 6.5 meters wide. They consisted of brick inside and outside, while the interior was filled with rubble. The later city walls, presumably built in the reign of King Narai, were only 1.5 meters in width and 6.5 meters in height from ground level up to crenelations. [19]





(Pom Pratu Khao Plueak and the northern city wall – Picture taken October 2024 CE)



Footnotes:

(1) Khlong Pratu Khao Plueak, 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). It was filled up somewhere in the early 20th century.
(2) 911 Chula Sakarat (CS) = 1549 Anno Domini (AD). AD = CS + 638.
(3) The technique of "mining" was used in warfare to bring down fortifications not built on solid rock. A tunnel was excavated under the outer defences either to provide access into the fortification or to collapse its walls. Temporary timber supports supported the tunnels as the digging progressed. When the excavation was completed, the wall or bastion which was undermined would be brought down by filling the excavation hole with combustible material. The combustibles, when lit, would burn away the pit props, leaving the structure above unsupported and thus liable to collapse. It is in this way that in 1767 CE, the walls near the Maha Chai Fortress were breached by the Burmese.
(4) Khlong Makham Riang, or the Canal of the aligned Tamarind Trees, was before called Khlong Nai Kai. It is a still-existent canal situated east on Ayutthaya's city island. The canal was a shortcut in the oxbow of the old Lopburi River. It has today its origin at Khlong Ho Ratana Chai below Wat Senasanaram and the Front Palace, and its mouth at the present Chao Phraya River, west of Phet Fortress. At the mouth was one of the eleven water gates of Ayutthaya called Pratu Nai Kai. The southern exit, which has today a water regulator, has been altered. The original mouth of the canal was about 170 metres south, close to Pom Phet. Khlong Makham Riang is one of the three large canals running north to south, of which two still exist.
(5) Wars with Lovek (Longvek) in 1570, 1575, 1578, 1581 and 1582 CE.
(6) Khu Khue Na, or the Front Moat, ran east of the city of Ayutthaya. The former defensive moat is said to have been dug in the reign of King Ramathibodhi I (U-Thong). More likely, it was the western defensive moat of the ancient Ayothya, situated in the oxbow of the Pa Sak River. The moat became thus a separation ditch (borderline) between the ancient city of Ayothya and the newly established city of Ayutthaya in the oxbow of the Lopburi River. At the establishment of Ayutthaya, the earthen walls surrounding the city were likely not further than the eastern defensive moat, later known as Khlong Pratu Khao Plueak.
(7) The Maha Chai Fort was first mentioned in the Royal Chronicles of Ayutthaya during the White Elephant War of 1563-64 CE. If the date in the chronicles is correct, then the fort must have defended the north-eastern part of the city. The fort stood likely not in its last known location but in the axis of the Khlong Makham Riang (Nai Kai) Canal, which was at that time the eastern city wall. Prince Damrong wrote that the Maha Chai Fort was erected around 1580 CE when the connection shunt was dug between the Lopburi River and the Khu Khue Na (Front Moat). There is thus a discrepancy with the Royal Chronicles of Ayutthaya. [Cushman, p. 35)
(8) La Mare was initially embarked to teach piloting to the marine guards of the embassy and apparently was not a trained engineer in France. He was, although, a gifted, self-made man and fell soon in the taste of Constantine Phaulcon. On arrival of the second French Embassy in 1687 CE - which was carrying four ‘Ingenieurs du Roi’ to the French general Desfarges - the works at the fort in Bangkok were already ongoing La Mare found him soon at loggerhead with Jean Vollant des Verquains, one of the four engineers working in Siam in 1687-1688 CE.
(9) Other sources (the testimonies) give only a height of 8 'sok' (4 meters) and indicate no width.





(Painting by Vingboons depicting Pom Phet before the shift from round bulwarks to angled bulwarks)



References:

[1] Cushman, Richard D. & Wyatt, David K. (2006). The Royal Chronicles of Ayutthaya. Bangkok: The Siam Society. p 15.
[2] Ibid. p. 28.
[3] Rajanubhap, Damrong (Prince) (1917). Our Wars with the Burmese. White Lotus, Bangkok (2000). p. 66.
[4] Cushman, Richard D. & Wyatt, David K. (2006). The Royal Chronicles of Ayutthaya. Bangkok: The Siam Society. p. 73.
[5] Ibid. p. 82.
[6] Wood, William A.R. - A History of Siam (1924) - page 128-30.
[7] Rajanubhap, Damrong (Prince) (1917). Our Wars with the Burmese. White Lotus, Bangkok (2000). p. 66.
[8] Baker, Chris Pombejra, Dhiravat na Van Der Kraan Alfons & Wyatt, David K. (2005). Van Vliet's Siam. Silkworm Books. p. 6.
[9] Jan Struys, The Perillous and most Unhappy Voyages of John Struys...., translated by John Morrison, London 1683.
[10] Terwiel, Barend Jan (2008). A Traveler in Siam in the Year 1655: Extracts from the Journal of Gijsbert Heeck. Silkworm Books.
[11] Cerutti, Pietro S.J. The Jesuits In Thailand. Part I (1607 - 1767).
[12] Gervaise, Nicolas (Paris,1688). The Natural and Political History of the Kingdom of Siam. Translated and edited by John Villiers (1998). White Lotus Press, Bangkok. p 31.
[13] Kaempfer, Engelbert (1727). The History of Japan (Together with a Description of the Kingdom of Siam). John Gaspar Scheuchzer. London. Hans Sloane, Praes. Soc. Reg. p. 27.
[14] Cushman, Richard D. & Wyatt, David K. (2006). The Royal Chronicles of Ayutthaya. Bangkok: The Siam Society. p. 480.
[15] Rajanubhap, Damrong (Prince) (1917). Our Wars with the Burmese. White Lotus, Bangkok (2000). p. 10.
[16] Tanabe, Shigeharu. Historical Geography Of Canal System In Chao Phraya River Delta. Journal of the Siam Society (JSS) 65. p. 41.
[17] Thompson, Peter Anthony (1910). Siam: an account of the country and the people. J. B. Millet, The Plimpton Press, Norwood, Mass., USA. p. 231.
[18] Phraya Boran Ratchathanin - Athibai Phaenthi Phra Nakhon Sri Ayutthaya kap khamwinitjai khong Phraya Boran Ratcha Thanin. Explanation of the map of the Capital of Ayutthaya with a ruling of Phraya Boran Ratchathanin. Revised 2nd edition and Geography of the Ayutthaya Kingdom. Ton Chabab print office. Nonthaburi (2007).
[19] Charnvit Kasetsiri & Michael Wright (2007). Discovering Ayutthaya. Toyota Thailand Foundation. p. 321.



When the past no longer illuminates the future, the spirit walks in darkness.
(Alexis de Tocqueville)





HISTORY OF AYUTTHAYA



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