The most important stupa in Muang Sing. It is said to contain the Adam's apple of Buddha. The date of when it was built is unknown. To the left of the stupa are some stairs which lead to a sacred fountain and a sacred stone. If you follow a path to the right of the stupa (be careful!) downhill you might be able to find the old moat and wall of the stupa. The biggest festival of the year, That Xieng Tung Festival, is held here every year during the full moon of the 12th lunar month (usually in late Oct or early Nov) and attracts a wide gathering from villages and people around the district and Luang Namtha province.