At the end of the alley stands Gringotts, a tall marble building run by goblins. The double front doors are made up of bronze, and upon entering you'll see a warning to "everyone who crosses the threshold." This warning sign is for anyone who plans on trying to rob from Gringott's vaults. The floor, much like the exterior, is a white marble up until you enter the vault section. Gringotts is one of the finest and safest places in the wizarding world. What is your vault number?