Wat Sibounheuang, the town's most evocative monastery, sports a lopsided gilded stupa and reclining Buddha in a delightful garden setting where the bare-brick ruins of the tiny original sǐm are reckoned to be from the early 14th century. The 'new' sǐm is covered in murals, including anti-adultery scenes in a style reminiscent of Matisse.
This building covers a mysterious 'hole' traditionally associated with singkhone spirit-ghosts who are placated in the Phaveth Festival (the 13th to the 15th day of the third Lao month) leading up to the February full moon.
