That Luang

The national shrine depicted in the national coat of arms is one of the most important Buddhist pilgrimage sites in the country.
According to tradition, missionaries of the Indian emperor Ashoka, who stayed here in the 3rd century BC, are said to have erected a reliquary for a splinter of bone from the sternum of Buddha.
The sacred stupa of That Luang was built in 1566 on Siamese models of the Sukhothai era, a few years after King Setthathirath moved the capital from Luang Prabang to Vieng Chan.

The original stupa was built on this site in 1566 by King Saysetthathirath and restored in 1953. The golden stupa is 45 meters high and is said to contain a relic of the Buddha. The golden centerpiece of this stupa resembles the curve of an elongated lotus blossom. Only the top is covered with real gold; the rest of the stupa is painted gold. Today, it is the most important national cultural monument in Laos.
Source: tourismlaos.org/that-luang