The United States Bullion Depository, more commonly known as Fort Knox, is a fortified vault building located next to the United States Army post of Fort Knox, Kentucky. The facility is operated by the United States Department of the Treasury. Gold reserves as well as other original historical documents and items have been stored there.

When the Japanese attacked Pearl Harbor in December 1941, a decision was made to move important historical documents to this location. Some of the documents included the signed originals of the Constitution of the United States and the Declaration of Independence, Articles of Confederation, President Abraham Lincoln’s Second Inaugural Address (autographed original), plus a Gutenberg Bible and an exemplified copy of the ‘Magna Carta’. These items were packed in crates and shipped by train to the depository on December 26, 1941.

The Treasury built the depository in 1936 on land transferred to it from the military. In keeping with a strategy to move gold reserves away from coastal cities to areas less vulnerable to foreign military attack, the first set of gold shipments to the depository transpired in the first half of 1937.

As a secure facility, between its fenced perimeter and granite lined concrete structure lies rings of razor wire and minefields. The grounds are monitored by high-resolution night vision video cameras and microphones. The subterranean vault is made of steel plates, I-beams and cylinders encased in concrete.

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