The Bureau of Engraving and Printing is where United States paper currency is printed. It is not a museum in the usual sense, but the public tour gives a rare look at the production lines, printing presses, and security processes behind the money in circulation.
It is a practical add-on to a National Mall day, especially for families or anyone interested in how government work happens behind the scenes. Tour access can change, so check the current schedule before building plans around it.