紹治帝
Thiên Mụ has been expanded many times over the years, and in 1710, the ruling lord Nguyễn Phúc Chu funded the casting of a giant bell, which weighs 3285 kg, and was regarded as one of the most prized cultural relics of its time in Vietnam. The bell is said to be audible 10 km away and has been the subject of many poems and songs, including one by Emperor Thiệu Trị of the Nguyễn Dynasty who ruled in the 1840s. Emperor Thiệu Trị, erected the Từ Nhân Tower in 1844, which is now known as the Phước Duyên tower. The brick tower stands 21 m and is of octagonal shape and has seven stories, each of which is dedicated to a different Buddha. The tower has stood there since, overlooking the Perfume River, and has become synonymous with the landscape of Huế and the Perfume River. Its impact is such that it has become the unofficial symbol of the city.