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 Lan Xang. Each year, a festival is held in That Phanom to honor the temple. This festival lasts for one week, during which thousands of people make pilgrimages to honor the shrine.
According to a Fine Arts Department marker on the site, it fell down in 1975, but was rebuilt with funds raised by public subscription, and from the government.
In Thai folk Buddhism, Wat Phra That Phanom is a popular pilgrimage destination for those born in the year of the Monkey. (Wikipedia; Wat Phra That Phanom)