Xieng Khaeng, in the Green Triangle across the Mekong from Myanmar, comprises 13 ethnic settlements. Steep mountains and the Mekong isolate this strip of Luang Namtha villages, though road access is possible via 57-km rugged road from Fang Mai on the Sing-Long road (Lao Route 17). There is no regular boat service, but cargo vessels occasionally stop at Xieng Khaeng, and some will accept passengers. Locals seem unwilling to charter their longboats to Xieng Kok in Long District.
In Muang Sing, you can jump on a combination tour that includes Mekong longboat rides stopping at Xieng Khaeng’s villages. These multiday programs also climb mountain trails to remote villages near the Chinese border.