Mushroom Kingdom Treasury
From the Super Mario Wiki
The Mushroom Kingdom Treasury, or just the Mushroom Treasury, is, as its name implies, the treasury hall for the entire Mushroom Kingdom government. Billions of Gold Coins are housed in the treasury's many rooms and compartments.
In The Adventures of Super Mario Bros. 3 episode "Crimes R Us", Bowser feels that his Koopalings have pulled enough "small crimes", and figures that it was time for them to pull the ultimate crime: stealing one billion gold coins from the Mushroom Kingdom Treasury.
While the Koopalings prepare to break into the treasury using a Bob-omb, a Chain Chomp, a Fire Snake and a Ptooie, Crimewave Clyde recruits his former foes Mario and Luigi into helping him stop the Koopalings. Arriving at the treasury before the Koopalings finally brake in, Clyde and the Marios wait for the Koopalings to discover them, only for them to be tied and returned to the Doomship, along with a Bob-omb surprise. With the Koopas gone, the robbery is foiled.