Wat Phra That Phanom is the sacred precinct of the Phra That Phanom chedi, located in the district of the same name, in the southern part of Nakhon Phanom Province, northeastern Thailand. According to legend, this structure contains The Buddha's breast bone, and as such, it is one of the most important Theravada Buddhist structures in the region. It was originally built in the 16th century by the Laotian King Setthathirath of Lanxang. Each year, a festival is held in That Phanom to honor the temple. This festival last for one week, during which thousands of people make pilgrimages to honor the shrine.