The name of Lohaprasada (Brazen Palace or Loha Prasat) is dated back as early as in India since Buddha's time. According to the definition by famed historian H.R.H. Prince Damrong Raganupab, it means"the structure with metal spires". Legend has it said that the first-ever multitiered square-shaped pagoda was built by Visakha, female Buddhist follower, in honour of the Buddha at Wat Bupharam in India. In B.E.328, King Tuttakamaneeapai ordered to have a second pagoda built in Sri Lanka. Today, the vestiges of two square-shaped pagodas still remain.
In Thailand, Loha Prasat is located at Wat Ratchanaddaram in Bangkok. The multi-tiered structure has a name for the cultural icon of Thailand as it is the third Loha Prasat in the world after two dilapidated predecessors. In modern days, Thailand's Loha Prasat is highly regarded as one of the world.
Located west of the ubosot (ordination hall), Loha Prasat was built in 1846 at the royal command of Kind Rama III. The structural design was in line with the description written in the Sri Lanka historical records. Somdet Chao Phraya Barommahapichaiyat (Tat Bunmak), who was earlier Phraya Sripipat Rattanaratkosa, was in charge of the construction. The construction workers were also sent to Sri Lanka for observation trip on its Loha Prasat. The imitation of the original pagoda was not the aim of the trip. Instead, the incorporation of the Thai craftsmanship into the design was greatly emphasized. Loha Prasat at Wat Ratchanaddaram is different from its two predecessors as it does not accommodate any monk. It is built to replace the old pagoda at the temple.
Loha Prasat has square-shaped pagoda blueprint in line with the Sri Lanka design, but the structural details are unlike. It is the seven-tiered with the third and fifth tier served as grottos and verandas. On the second, fourth, and sixth tier, there are porches with 12 metal spires when the Buddha relics are placed on the top. In total, the pagoda has 37 metal spires, which are indicative of 37 virtues of Buddhist principles toward the enlightenment.
The spiral staircase in the middle of the pagoda is the access to the top of Loha Prasat. The large log serves as a center pole for the staircase. Since the construction in the reign of King Rama III, it never neared completion until the King Rama IX when the first restoration was in 1963.
