It is a group of structures consisting of a pagoda and a tower built in the middle of a square lake. The whole group was officially called Dien Huu Pagoda and Lien Hoa Tower, but the tower has traditionally been called the One-Pillar Pagoda. It is of a square shape and each side is nine feet long with a curved roof placed on a round stone pillar. The pillar is approximately 4 feet in diameter, twelve feet high (excluding the underground section) supporting a system of beams of timber, thus making up a framework for the tower resembling a blossoming lotus stretching up out of the square pond that has a surrounding brick wall. From the edge, there is a narrow brick path running through the pond to a nice ladder leading up into the Buddhist tower where there is a notice reading that the Lotus tower and pagoda were built in memory of a dream had by King Ly. The inscription states "King Ly Thai Tong (1028-1054) dreamt of seeing the Quan An Buddha sitting on a lotus tower to which the King was led. Upon waking, the King told his lords about his dream and sought their advice. Some of them advised him to build a stone pillar in the middle of the pond and place a Buddhist's lotus tower on the pillar just as the King had dreamt." Then Buddhist monks were asked to pray and worship for the King's longevity. Consequently, the pagoda was called "lasting life" (Dien Huu) and that took place in 1049.
The One-Pillar Pagoda has undergone numerous changes and repairs. On September 11, 1954 before their withdrawal, the French army mined and destroyed the Lien Hoa Dai. When the liberation forces took over Hanoi, the government rebuilt the pagoda in accordance with its original structure and completed it in April 1955.
