
The Cambodia–Laos border is the international border between
Cambodia
Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailan ...
and
Laos. The border is 555 km (345 m) in length and runs from the
tripoint
A tripoint, trijunction, triple point, or tri-border area is a geographical point at which the boundaries of three countries or subnational entities meet. There are 175 international tripoints as of 2020. Nearly half are situated in rivers, l ...
with
Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...
in the west to tripoint with
Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making it ...
in the east.
Description
The border starts in the west at the tripoint with Thailand at Preah Chambot peak in the
Dângrêk Mountains
The Dângrêk Mountains (; km, ជួរភ្នំដងរែក, ; th, ทิวเขาพนมดงรัก, ), also the Dângrêk Range, is a mountain range forming a natural border between Cambodia and Thailand.
Geography
Despi ...
.
The border then proceeds overland to the south-east, reaching the Tonle Repou river and following this eastwards to the
Mekong River
The Mekong or Mekong River is a trans-boundary river in East Asia and Southeast Asia. It is the world's twelfth longest river and the third longest in Asia. Its estimated length is , and it drains an area of , discharging of water annual ...
. The Mekong here is extremely wide, forming the
Si Phan Don The Si Phan Don ( lo, ສີ່ພັນດອນ; meaning '4,000 islands') is a riverine archipelago in the Mekong River, Champasak Province in southern Laos. Si Phan Don is part of Khong District, including the islands and part of the mainlan ...
islands area, with the border along the southern rim of this riverine lake, before leaving it and proceeding overland to the north. The border then turns east, reaching the
Kong River
:''Cong River (''sông Công'') is a river in Central Vietnam''
The Kong River, also known as the Xe Kong or the Se Kong ( Lao: ເຊກອງ ''Se Kong'', ( Khmer:''សេកុង''(official) or ''ស្រែគង្គ''(Khmerization)), V ...
and following this for a period, before proceeding eastwards over to the Vietnamese tripoint in the
Annamite Mountains.
History

From the 1860s
France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...
began establishing a presence in the region, initially in modern
Cambodia
Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailan ...
and
Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making it ...
, and the colony of
French Indochina
French Indochina (previously spelled as French Indo-China),; vi, Đông Dương thuộc Pháp, , lit. 'East Ocean under French Control; km, ឥណ្ឌូចិនបារាំង, ; th, อินโดจีนฝรั่งเศส, ...
was created in 1887.
Laos was at this point part of the
Kingdom of Siam Kingdom of Siam may refer to:
* Sukhothai Kingdom (1238–1351)
* Ayutthaya Kingdom
The Ayutthaya Kingdom (; th, อยุธยา, , IAST: or , ) was a Siamese kingdom that existed in Southeast Asia from 1351 to 1767, centered around the ...
(the old name for Thailand), however all areas east of the Mekong were
annexed to French Indochina in 1893 following the
Franco-Siamese War
The Franco-Siamese War of 1893, known in Thailand as Incident of R.S. 112 ( th, วิกฤตการณ์ ร.ศ. 112, , ) was a conflict between the French Third Republic and the Kingdom of Siam. Auguste Pavie, French vice consul in Luan ...
.
In 1905 the southern Lao regions of
Stung Treng
Stung Treng City ( km, ទីក្រុងស្ទឹងត្រែង) ( lo, ຊຽງແຕງ ) is the capital of Stung Treng Province, Cambodia. It is the major city (and capital) of both the district and province.
Geography
Stung Tren ...
and
Ratanakiri were transferred to Cambodia based on their historical affiliation to the Khmer kingdom, with a small area going to Vietnam.
It is thought that the French authorities thereafter used the historic boundary of Stung Treng province as the Cambodia–Laos border, though as it was at this point merely an internal administrative line running through a remote area there was no pressing need to define it in detail.
Both Laos and Cambodia gained independence in 1954 and the border became one between two sovereign states.
The border area was volatile throughout much of the 1950s-80s owing to the various conflicts in Indochina.
There were also tensions over irredentist Lao claims to Stung Treng, with Cambodia conducting a Khmer-isation campaign in the region in the 1950s-60s.
As a result no demarcation took place and Lao-Cambodian relations remained frosty, deteriorating further during the rule of the nationalist-Communist
Khmer Rouge
The Khmer Rouge (; ; km, ខ្មែរក្រហម, ; ) is the name that was popularly given to members of the Communist Party of Kampuchea (CPK) and by extension to the regime through which the CPK ruled Cambodia between 1975 and 197 ...
in Cambodia from 1975-79.
In 2000 the two countries announced that they would start work on demarcating the border.
Whilst much work has been done, by late 2019 there were parts of the border still undemarcated.
Border crossings
There is currently one official crossing point, at Nong Nok Khiene (Laos) - Tropaeng Kreal (Cambodia).
See also
*
Cambodia–Laos relations
References
{{DEFAULTSORT:Cambodia-Laos border
border
Borders are usually defined as geographical boundaries, imposed either by features such as oceans and terrain, or by political entities such as governments, sovereign states, federated states, and other subnational entities. Political bo ...
Borders of Cambodia
Borders of Laos
International borders