Fort Knox

Fort Knox was an establishment containing Earth's largest gold repository before the New World Economy took form in the late-22nd century.

It was located in the state of Kentucky of the United States of America. At its peak, it held upwards of 50 metric tons of bullion. It became a museum after the New World Economy formed. It was considered virtually impenetrable despite an attempt by Ferengi to break in in 2365.

In 2375, while planning a heist of a Borg transwarp coil, Captain Janeway of the USS Voyager used Fort Knox as a metaphor to explain the scale and the level of security around the prize they sought. Some of the staff did not understand what Janeway meant, requiring Tom Paris to explain. In light of this, Captain Janeway named their mission "Operation Fort Knox". 

Apocrypha

 * According to the novelization of Star Trek: First Contact, following the Third World War, the gold reserves of Fort Knox had been depleted to the point of nonexistence.