Gringotts

The wizarding bank located in Diagon Alley, Gringotts was owned and operated by goblins. Dating back to 1474 the cavernous tunnels lead miles underground and stretch out beneath the streets of London, with the highest-security vaults located the deepest. The carts, used to navigate the mine-like deep tunnels, and keys, used to open the vaults, can only be operated by goblins. Although Gringotts was arguably one of the safest places in the wizarding world (as Hagrid said, "yeh'd be mad ter try an' rob it"), it has been subject to breaches of its security.