Phra That La Nong, also known as the Middle Mekong Stupa or the Central Stupa, is an ancient stupa that has housed sacred relics of the Buddha for many centuries. Originally situated on the riverbank at Wat Phra That Nong Khai, it collapsed into the Mekong River due to erosion in 1847. The stupa is now submerged about 200 meters from the shore and is visible during the dry season. A replica has been built on land to commemorate this historic stupa and to honor Her Majesty Queen Sirikit on her 72nd birthday. The interior of the replica houses a seven-tiered golden parasol created to honor King Bhumibol Adulyadej on his 84th birthday.