Fort Knox is known for the United States Bullion Depository, or affectionately known as the “Gold Vault”. With its impenetrable security and super secret persona, it makes it the perfect place to house the largest portion of the United States’ gold reserve. Constructed in 1936 for the purpose of gold storage, it briefly secured the original Declaration of Independence, US Constitution, the original Gettysburg Address, three volumes of the Gutenberg Bible, and Crown Jewels. The vault door weighs more than 30 tons, is 25 inches thick, and no one person knows the complete combinations required to unlock the vault. The fortress houses a separate emergency power plant, water system and takes a presidential order to gain access. The endless layers of security include, alarms, video cameras, microphones, minefields, barbed razor wire, electric fences, heavily armed guards and the Army units that are based there. Whew!!! Now we know where the old saying “That's like breaking into Fort Knox” comes from! In April 2016, Fort Knox holdings were 4,582 metric tons (147.3 million oz. troy). At the rate of $1,226.60 an ounce it is worth about $180 billion! To learn more check out this great video on the history of Fort Knox.