evidence: The province of Stung Treng marks Cambodia's northern border with Laos and the point where Mekong River enters Cambodia after swirling its way around the 4000 Islands (Si Phan Don) area of southern Laos. Steung Treng (River of Reeds) province is located remotely in the northeast of Cambodia. The province of Stung Treng marks Cambodia's northern border with Laos and the point where Mekong River enters Cambodia after swirling its way around the 4000 Islands (Si Phan Don) area of southern Laos. [...] Steung Treng was formerly called Xieng Teng and was once a part of the vast Khmer Empire, then the Lao kingdom of Lan Xang and later the Lao kingdom of Champassack. After the Franco-Siamese war of 1893, Chiang Taeng (Stung Treng) was administered by French Lower Laos from 1893 to 1904.