Wat Ratchanatdaram is a Bangkok royal temple best known for Loha Prasat, the metal castle. Its unusual spires and concentric plan make it one of the most distinctive buildings in old Rattanakosin.
The temple was built under King Rama III for his granddaughter, Princess Somanass Waddhanawathy. The SAC record dates Loha Prasat's first construction to 1851 and notes that later restoration completed the structure.
Loha Prasat is a three-storey brick-and-stucco building with 37 metal spires and a spiral route through its levels. The design draws on older Buddhist metal-palace models that no longer survive in their original form. Check current access arrangements before treating the upper levels as open.