The 
Super Star Destroyer, a large mobile craft in the fictional 
Star Wars universe, is a truly gargantuan spaceship carrying thousands upon thousands of crew, shown in the movies as over 17 kilometres long though often quoted at only 8 km in secondary sources.  
Darth Vader's command ship, the 
Executor, was the only such vessel featured in the movies.  It was involved in the siege of 
Hoth in 
The Empire Strikes Back, and the 
Battle of Endor in 
Return of the Jedi. The ship was destroyed by the Rebels as part of the Battle of Endor, colliding with the second 
Death Star after its bridge was destroyed by a crashing A-wing fighter.  
This ship however had a cousin the Lusankya.  The Lusankya was buried on Coruscant by Emperor Palpatine unknown to the entire galaxy.  There are larger ships other than the Death Star, there is the Sovereign-class Super Star Destroyer which features a part of the Death Star's main weapon.
- See also : Star Wars
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