Loha Prasat Castle is a Buddhist temple located between Ratchadamnoen Klang and Mahachak Roads, in the Phra Nakhon district of Bangkok. The name of the temple means “Royal Niece”, for it was built by King Rama III in 1846, for his niece, the princess Mom Chao Ying Sommanus Wattanavadi. There is an amulet market at Wat Ratchanaddaram. Wat Ratchanaddaram’s best known component is the uniquely shaped pagoda called Loha Prasat.
It is a multi-tiered structure 36 m high and having 37 metal spires, signifying the 37 virtues toward enlightenment. In 2005, the temple was submitted to UNESCO for consideration as a future World Heritage Site.