That Makmo, the "watermelon" stupa, is the nickname given to this building dating from 1503. It is the only monument in Laos to have adopted the rounded shape of Sinhalese stupas - hence its more popular name. Its actual name is in fact That Pathoum, the stupa of the Great Lotus. The stylised flame crowning it symbolises the illumination of the Buddha. Lightning gutted the stupa in 1914, when precious offerings were revealed here, including gold and crystal statuettes.