Houay Xai (also Huay xai, Houei Sai, etc) is the capital of the Laos province of Bokeo. It lies on the banks of the Mekong river, which forms the border to Thailand.
The town lies on the Mekong River opposite Chiang Khong in Thailand. The Fourth Thai–Lao Friendship Bridge ( on the stamp) at Ban Houayxay, which opened in December 2013 and replaced ferry service across the river, is now the northernmost border crossing between the two countries
The 4th International Mekong Bridge