Located on Gold Vault Road, approximately 30 miles southwest of Louisville
, this depository holds a large portion of the U.S. gold reserve. The two-story 100-foot-square, circa 1936 treasure house is bombproof; its walls and roof are faced with huge granite blocks lined with concrete and steel. The building contains a two-level steel and concrete vault, which is divided into compartments and sealed with a door weighing over 20 tons; the vault must be opened by several staff members, each of whom has a separate portion of the combination. At different times the vault has also held the British Crown Jewels, the Magna Carta, the Constitution of the United States and the Declaration of Independence.
Outside, four guard boxes are located at each corner of the structure, which is surrounded by steel fencing, and sentry boxes are located at the entrance gate. The depository site, formerly part of the Fort Knox military reservation, is closed to the public.