The most characterful of Hongsa's several monasteries is Wat Simungkhun. Its hang song pa (initiation pavilion) is fashioned in attractive naive style while the archaic, muralled sǐm (ordination hall) sits on an oddly raised stone platform covering a large hole that is said to lead to the end of the world. It's 1km west of the centre towards Muang Ngeun, then 100m north after the first river bridge.