Rattanakosin Island, the historic heart of Bangkok: a capital shaped by water, contested by its memory

On 21 April 1782, on the eastern bank of the Chao Phraya, a wooden pillar is planted in the ground. This act founds the capital of the new Chakri dynasty. Around that point a singular territory takes shape: an ‘island’ closed off to the east by man-made moats. It holds the Grand Palace and major temples, and for a long time it was also a place of everyday life. To understand Rattanakosin is to read how a river, canals and ramparts shaped a city. It is also to see how, since the 1970s, the desire to conserve this historic heart has raised a delicate question: which past are we protecting, and for whom?

An island made by human hands

On a map of Bangkok, Rattanakosin Island is not immediately easy to spot. No branch of the river cuts it off naturally. It occupies the eastern bank of the Chao Phraya, in what is now Phra Nakhon district, where the river bends into a meander. To the west, the river forms its edge. To the east, it is bounded by khlong (canals) dug to link two points on the bank and so close the loop. The ‘island’ is therefore artificial: it is as much a military and political construction as a geographical fact.

Here are concentrated the sites one instinctively associates with royal Bangkok: the Grand Palace, the Temple of the Emerald Buddha (Wat Phra Kaew), Wat Pho, the vast open ground of Sanam Luang and the City Pillar Shrine. Yet the island cannot be reduced to these monuments. It has also been a place of neighbourhoods, shops and communities, and this dimension lies at the heart of current debates.

Two belts of water

The arrangement rests on two successive moats.

• The inner belt is Khlong Khu Mueang Doem, literally ‘the old city moat’. As its name suggests, it is a ditch inherited from Thonburi, the previous capital, which protected the part of the city lying on this bank. It marks the inner limit of the island.
• The outer belt is Khlong Rop Krung, ‘the canal that encircles the capital’, dug under the first king of the Chakri dynasty. This single waterway changes its name from one stretch to another: it is called Khlong Bang Lamphu in the north and Khlong Ong Ang in the south. It joins the Chao Phraya at both ends. The southern stretch, 1.826 km long, is said to have been completed in 1783 and has recently been redeveloped.

This double water enclosure explains the vocabulary still used by urban planners. They distinguish an ‘inner’ and an ‘outer’ Rattanakosin, to which the most recent plans add the Thonburi bank opposite and extension zones. The organisation of space is concentric: at the centre, power and the sacred; around it, successive rings that have absorbed the city's growth.

1782: crossing the river to found a capital

From Thonburi to the eastern bank

For fifteen years, from 1767 to 1782, the capital of the Siamese kingdom was Thonburi, on the western bank. It had a single sovereign, Taksin. In 1782 a senior military dignitary, Chao Phraya Chakri, seized power and became the king known as Rama I (Phra Phutthayotfa Chulalok). The change of reign was accompanied by the death of Taksin. The circumstances of his end are the subject of divergent accounts, and the matter remains sensitive in Thailand. The Thai press points out that the execution of his predecessor preceded the founding of the new capital by only a few weeks.

The new king decided to move the seat of power to the eastern bank, considered easier to defend. The logic was strategic: backed by the river and closed off by moats, the new city lent itself to a coherent enclosure. It also marked a symbolic break with the previous reign.

This move came at a human cost. Chinese merchants had already settled on the site chosen for the palace. They were moved further south-east, to the area between Wat Sam Pluem and Wat Sampheng, which would become Bangkok's Chinatown. According to the Siam Society, they were allocated nearby land and do not appear to have offered any resistance. The episode is telling: from the very outset, the creation of the royal centre involved reorganising the populations who occupied the space.

The City Pillar, a birth certificate

The official founding of the capital is dated to the raising of the lak mueang (city pillar) on 21 April 1782. This date is commemorated every year as the anniversary of Bangkok as capital. The precise moment of the ceremony was set by the court astrologers. The sources do not, however, agree on the exact time. The daily Thairath and the Khaosod English website, which draws on the royal astrologers' records as cited by the historian Rome Bunnag, give 6.54 am. Other compilations give 6.45 am. Only the royal chronicle of the First Reign could settle the matter.

The pillar was carved from chaiyaphruek wood, a species that some English-language sources render as ‘Java cassia’. Its shrine stands at the south-eastern corner of Sanam Luang, facing the Grand Palace. According to some encyclopaedic sources, it was the very first building of the new capital, predating the palace itself. The claim is plausible given the pillar's function, but it needs to be confirmed by a primary source.

Around this act have grown interpretations that belong to tradition. Thairath presents the chosen moment as placed under a sign of ‘victory in war’, with Aries in the ascendant: this is an astrological interpretation, not a historical fact. Khaosod English has also relayed, from a book by Rome Bunnag, a tale of a ‘curse’ attached to the ceremony. It should be read as an urban legend. It bears witness to the symbolic charge of the place, not to the reality of events.

Ramparts, forts and canals: the city overflows

The enclosure of the 1780s

After the moats came the walls. In the 1780s the capital surrounded itself with ramparts punctuated by pom (forts). Several bear names still familiar to Bangkok residents: Phra Sumen, in the north, at the mouth of Khlong Bang Lamphu; Mahakan, built in 1783 near today's Phan Fa Lilat Bridge; Phra Chan and Phra Athit, along the river; Maha Yak, near Wat Pho. The exact number of original forts and the list of those that survive have yet to be established precisely. Phra Sumen and Mahakan are, at any rate, among the rare visible remains of this defensive belt.

This is the landscape of a fortified water city. The river serves as a thoroughfare and a first line of defence. The canals act as moats, but also as routes for transport and drainage. The walls complete the system where water is not enough.

1851–1852: a new ring, without ramparts

A generation later, the city had outgrown its limits. Under Rama IV, in the early 1850s, the minister Chaophraya Si Suriyawong had Khlong Phadung Krung Kasem dug as a new outer moat. This time, however, ramparts were not built: such defences were considered obsolete. Seven forts were deemed sufficient, plus an eighth on the opposite bank.

This choice is a valuable clue. By the mid-19th century the nature of the threat had changed. The walled enclosure ceased to be the model for protecting the capital, and the canal became first and foremost an urban boundary and a means of communication. Rattanakosin Island then shifted from being the whole city to being the historic core of an expanding metropolis. It is this core that the 20th century would seek to protect.

Protecting the heart: half a century of conservation plans

Successive committees and plans

Conservation of the island became public policy in the late 1970s. On 4 July 1978 the Council of Ministers appointed a committee responsible for Rattanakosin and old towns. The capital's bicentenary in 1982 acted as a catalyst: according to the archives of the Fine Arts Department (FAD), the state heritage administration, conservation and renovation plans were then drawn up for nine selected monuments.

Several planning documents followed. In 1994 a master plan for the conservation and development of ‘Krung Rattanakosin’ (krung means the capital) was produced by a consultancy for the office responsible for environmental policy, then attached to the Ministry of Science. A document from the United Nations Economic and Social Commission for Asia and the Pacific (UNESCAP) dates the formation of the ‘current’ Rattanakosin committee to 1996. This is probably a reconstitution of the body created in 1978, but the line of descent between the two remains to be verified. A master plan covering the inner and outer zones was adopted in 1997, followed by another for the Thonburi bank in 2000.

In the latest stage, the Office of Natural Resources and Environmental Policy and Planning (ONEP) drew up in 2018 the strategies for a master plan running to 2032, the year of the capital's 250th anniversary. This plan, presented to the Council of Ministers around 2020, is to be implemented over fifteen years.

One island, several perimeters

This administrative history explains why very different surface areas are encountered. According to the UNESCAP document, based on data from the mid-1990s, the area managed by the committee covers 5.84 km². The 2032 plan, for its part, adopts a perimeter of 9.98 km². It comprises five zones: inner Rattanakosin, outer Rattanakosin, the Thonburi bank opposite and two extension zones. The two figures do not contradict each other: they reflect a gradual widening of what is regarded as the historic heart, now conceived on both sides of the river.

The 2032 plan: a broader ambition

As its designers present it in the journal Nakhara (Peerapun et al., 2020), the 2032 plan sets out the vision of a ‘glorious capital’. It aims to bring together urban heritage, the plurality of local cultures and contemporary planning. Its eight objectives include tourism management and residents' quality of life. The approach is intended to be participatory, involving communities, temples and schools. The text refers explicitly to ICOMOS's Valletta Principles, which concern the safeguarding of historic towns. The plan also incorporates intangible heritage.

Governance nevertheless remains complex. It involves the FAD, the conservation committee, the Bangkok Metropolitan Administration (BMA) and ONEP. The limits of this system have become apparent on several occasions. In 2019, with regard to Ayutthaya, the FAD lamented that it had no legal role at the initial stage of major infrastructure projects. In 2023, according to the Bangkok Post, it voiced concern over the route of the Purple Line metro near the historic area.

Mahakan Fort, or the question of what we conserve

An implicit ‘charter’

The architectural historian Chatri Prakitnonthakan offered a critical reading of this policy in the Journal of the Siam Society (vol. 100, 2012). In his view, conservation of the island follows a never-written ‘Rattanakosin charter’. Heritage created by the monarchy is systematically placed above that of other social groups. He sees its mark as early as the 1982 bicentenary plans. He cites in particular two projects in the master plan: demolishing shophouses to open up the view of the Golden Mount (Phu Khao Thong) and laying out a park at Mahakan Fort. These projects, he argues, were contested from the outset, both within academia and beyond. He also denounces a ‘double standard’ and public agencies too closely linked to one another to hold each other to account.

This reading is an interpretation, well argued but disputed. The plans' advocates would counter with the aim of showcasing the major monuments and, more recently, the 2032 plan's stated openness to local cultures. The case of Mahakan Fort allows these two visions to be set against each other.

Twenty-six years of conflict

At the foot of the 1783 fort, one of the last remains of the enclosure, lived a community of nearly 300 people. According to its residents' account, their settlement dated back to the reign of Rama III, when servants of aristocratic families are said to have settled there. This is a community tradition, not a proven fact. Defenders of the site highlighted old wooden houses, some of which, they claimed, dated from the early Rattanakosin era.

The conflict arose from an ‘embellishment’ project in the 1990s and lasted twenty-six years. Having acquired the land through compulsory purchase, the BMA consistently won its case in the courts. It disputed both the historical value of the site and its very status as a ‘community’. It stressed that many residents had arrived recently, some from Isan, the large north-eastern region. The eviction deadline was set for 25 April 2018. On 24 July that year, a 6,400 m² public park opened in place of the homes.

A bitter outcome

The outcome did not close the debate. In an editorial, the Bangkok Post judged the park a failure, barely used, and considered that the BMA had implicitly acknowledged its mistake. A participatory digital archive was created to preserve the community's memory. The episode illustrates the tension identified by Chatri Prakitnonthakan: a military monument from the founding is showcased at the expense of an inhabited fabric whose age and legitimacy remained contested.

Beyond the monuments: a living, ordinary heritage

Recent approaches tend to widen the lens. A study published in 2023 in Frontiers of Architectural Research looks at the island's ‘ordinary’ heritage: its modest restaurants and everyday cooking. This shift is significant. It treats practices and know-how as heritage, not just buildings.

The FAD itself is stepping up initiatives to promote the area. It has launched the Rak Nakhara, Makkha Haeng Rattanakosin route, which might be rendered as ‘Love the City, Path of Rattanakosin’. The trail starts from the department's former building near Sanam Luang and links museums, galleries and performance venues. It was inaugurated on Mother's Day, 12 August, by the director-general, Phanombootra Chandrajoti. Near Wat Phra Kaew, roadworks uncovered 130 old stone statues depicting various nationalities and mythical creatures. They were excavated and restored by the FAD, then installed within the temple grounds. A 96 m underpass now displays a map and old photographs of the area. The ground beneath the city thus itself becomes a place of urban storytelling.

Rattanakosin Island ultimately emerges as a palimpsest. In it one can read the strategic decision of 1782, the belt of water and brick of the early decades, and then the city's spilling beyond that enclosure in the 19th century. Added to these, finally, are the conservation policies, which have fixed a symbolic centre while at times emptying it of its inhabitants. Even its boundaries have changed: 5.84 km² yesterday, nearly 10 km² in the 2032 plan, which now includes the other bank. The challenge of the coming decade, up to the 250th anniversary, lies less in restoring the monuments, already largely under way, than in the ability to make the royal capital, the city of neighbourhoods and the city of modern transport coexist, as the metro debate shows.

Sources and further reading

1. W. Peerapun, S. Sereerat, P. Sanit, P. Vichienpradit, Master Planning for Conservation and Development of Krung Rattanakosin 2032, Nakhara: Journal of Environmental Design and Planning, vol. 19 (ThaiJO), 2020.
2. Chatri Prakitnonthakan, Rattanakosin Charter: The Thai Cultural Charter for Conservation, Journal of the Siam Society, vol. 100, 2012.
3. non indiqué, Traffic and transportation for Sustainable Environment… (étude de cas Rattanakosin), UNESCAP (Nations unies), non indiqué.
4. The Siam Society, Discovering Thonburi's Lesser-Known Temples and Buddhist Mural Paintings, The Siam Society under Royal Patronage, non indiqué.
5. Thairath, April 21 Marks 244th Anniversary of the Founding of Rattanakosin Kingdom: Historical Background, Thairath English, 2026.
6. Khaosod English, The Curse That Haunted Bangkok 150 Years – Until Now?, Khaosod English, 2017.
7. Bangkok Post, Saving the Fort Mahakan community, Bangkok Post, non indiqué.
8. Bangkok Post (éditorial), The Mahakan Fort mistake, Bangkok Post, non indiqué.
9. Prae Sakaowan, History Lost: The end of the centuries-old Mahakan Fort community, Coconuts Bangkok, 2018.
10. Coconuts Bangkok, Bangkok's Mahakan Fort reopens today as public park, Coconuts Bangkok, 2018.
11. The Nation, Bangkok heritage route links museums, textiles and theatre, Nation Thailand, non indiqué.
12. Bangkok Post, Celebrating Rattanakosin art, Bangkok Post, non indiqué.
13. Contributeurs Wikipédia, Rattanakosin Island, Wikipedia (encyclopédie collaborative, à recouper), consulté 2025.
14. Contributeurs Wikipédia, History of Bangkok, Wikipedia, n.d..
15. Contributeurs Wikipédia, Bangkok, Wikipedia, consulté 2025.
16. Contributeurs Wikipédia, Fortifications of Bangkok, Wikipedia, consulté 2025.
17. Contributeurs Wikipédia, Khlong Ong Ang, Wikipedia, consulté 2025.
18. Contributeurs Wikipédia, Ubonrat Bridge (Khlong Khu Mueang Doem), Wikipedia, consulté 2025.
19. Contributeurs Wikipédia, Khlong Phadung Krung Kasem, Wikipedia, consulté 2025.
20. Contributeurs Wikipédia, Lak Mueang, Wikipedia, consulté 2025.
21. SEAArch, Tag: Rattanakosin (Old Bangkok) – relais de « Purple Line plans worry art chiefs » (Bangkok Post, 15 avril 2023), Southeast Asian Archaeology, 2023.
22. non relevé, Ordinary Urban Heritage of Rattanakosin: Ordinary restaurants and everyday foods of the historic center of Bangkok, Frontiers of Architectural Research (Elsevier/ScienceDirect), 2023.
23. Bangkok Post (éditorial, via inkl), Heritage went off the rails, Bangkok Post / inkl, non indiqué.
24. The Nation, Mahakan Fort Community to live on in the virtual world, Nation Thailand, non indiqué.