Delving citadels, also known as delving-citadels, were a type of vehicle used by ore-dukes to mine on the planet Shu-Torun. During the War on Shu-Torun, the Galactic Empire destroyed one of the citadels belonging to the dukes, also horrifying their ally Queen Trios, who knew that the vehicles would be needed after the war to meet Imperial quotas. She asked the Sith Lord Darth Vader to stop destroying the citadels, but was refused. She later requested that the citadel of Baron Rubix be the second to be targeted, as he had attempted to have her killed.