What type of structure does North Carolina Granite Corporation Quarry Complex and United States Bullion Depositor have in common?
North Carolina Granite Corporation Quarry Complex: North Carolina Granite Corporation Quarry Complex is a historic granite quarry and national historic district located at Mount Airy, Surry County, North Carolina. United States Bullion Depository: The United States Bullion Depository, often known as Fort Knox, is a fortified vault building located within the United States Army post of Fort Knox, Kentucky.
building