First built in 1649, the conch shape watchtower (or Ta-Dzong) was established to protect the Paro Dzong (Fortress) below by overlooking the entire Paro valley from all directions. Conch shell has been the horn trumpet in Buddhism since the beginning of time. The conch shape design encompasses the union of sun (circular shape outside) and moon (crescent shape inside) which symbolizes fame and victory, making it very meaningful as a watch tower.
In 1950s, the watch tower was closed to a collapse state. The third king ordered a renovation project to enhance the structure of the building and turned it into the National Museum. It now houses historic artifacts, antiques, ritual objects used in traditional festivals, as well as some preserved specimens of animals in Bhutan.