In 1995, 17 antique Siamese maps were discovered in the Grand Palace. Ironically, the people who found these rare old maps weren't even looking for them. On a search for old court textiles for an exhibition, officials stumbled upon some cotton sheets with elaborate markings in a cupboard in the Princess Abhantri Paja Mansion, royal residence of a daughter of King Rama V.

The cotton sheets turned out to be antique Siamese maps. The discovery of these maps started a quest for their origin and purpose that was to last almost 10 years. The officials presented the maps to the Crown Princess who tasked Santanee Phasuk, a geography teacher at Chitralada School to embark on this mission.

In 1997, Santanee went on a royally sponsored doctorate in cartography to research on these maps at the School of Oriental and African Studies, University of London.

Together with Professor Philip Scott, Head of the Geography Department in the same university, Dr Santanee researched and analyzed the old maps, which covered Burma, Thailand Indochina and China.

Characteristics of the old maps

The old maps are hand drawn and hand painted on large cotton sheets with names written in Thai script. The maps consist of topography maps with the terrain features painstakingly marked, coastal maps and even a chart of a battle plan!

Muang Tawai (Tavoy, Myanmar) is the largest map on display, at 4 x 5 m showing the western border province of Kanchanaburi, River Kwai and Three Pagoda Pass, the traditional invasion routes of Burma into old Siam. The area was the scene of frequent battles during the Siamese-Burmese Wars in the reign of King Rama I.

Saiburi (Alor Setar, Kedah) is the only display that's not an actual map but a detailed chart of a battle plan to capture a coastal fort in what is now Peninsula Malaysia. It was the battle plan of the Siamese expeditionary force to put down a Muslim revolt in southern provinces.

The chart denotes details of enemy cannon and forces, deployment of Siamese ships and forces, the attack plan, including the assault and scaling parties for the walls. The chart even records the outcome of the battle and casualties. The name of rebel leader on the chart matched that of a rebel leader during the reign of King Rama III.

Khemen Nai Ni (Cambodia) covers famous Angkor Wat and Tonle Sap, the lake that drains and fills during the dry and rainy seasons. The positions of Angkor Wat and other temples and Tonle Sap with all its tributaries are clearly marked in detail.

The area covers the Cambodian provinces of Battambang and Siem Reap over which several wars were fought. These territories were in dispute right up till the 1940s.

Of the five antique Siamese maps, Muang Jin (China) is the most fascinating. The 2x4 m piece covers the entire coastline from Thailand to southern China, Hong Kong and Taiwan, all the way to Japan and Korea, including the northern tip of Luzon, Philippines. The coastline has been accurately mapped with details of all the coastal inlets.

Muang Kwantung (Guangzhou, China) is a city map of old Canton, showing the Pearl River delta, location of factories and buildings in the city.

Purpose of antique Siamese maps

The topography maps on border areas with Burma and Cambodia, traditional foes, were obviously for military purposes, the military routes and terrain features mapped by military commanders during campaigns to assert territorial claims or suzerainty.

Trade with China, the major trading partner then, required navigation charts mapped by ship captains and surveyors hugging the coast to China on a 30 40 day round trip.

Accuracy of old maps - direction, distance and location

Military routes and distances were generally accurate as these were physically traversed. Locations of terrain features, mountains, jungles and rivers were also accurate.

The scale of these antique Siamese maps was compared with modern maps; the directional error was 1 degree, quite a mapping feat given the technology of those days.

Period of antique Siamese maps

The period of these maps was determined by a through detailed analysis of the hand-written Thai script, the consonants, vowels, tone marks used then and the writing styles.

The use of obsolete consonants, the cursive writing style and predominance of the first two tonal sounds in the Thai language indicate that the period of these old maps during the reigns of the first three Chakri kings i.e. around the late 18th the early 19th centuries.

This rare collection of antique Siamese maps is remarkable as there are very few maps of these areas before the early 19th century. The collection is kept in the personal library of the Crown Princess.

On special occasions they are put on public display. A public exhibition of antique Siamese maps was held at the Jim Thompson House from February - March 2006 when five of the 17 maps were displayed.