Sanjusangen-do is officially known as Rengeō-in. A Tendai Buddhist temple, it was built in 1164 to house 1001 statues of Kannon, the Buddhist goddess of mercy. A fire in 1249 destroyed the hall and most of the statues, and reconstruction was completed in 1266.
Though the golden statues are said to have one thousand arms apiece, most visitors notice fairly quickly that they have only forty. The Buddhist formula is that each arm can save an impressive 25 worlds.