Maw Station

Built from asteroids in the midst of the Maw, Maw Installation was an Imperial think tank established by Grand Moff Wilhuff Tarkin for the creation of superweapons. 
It was defended by Admiral Daala and her fleet of Star Destroyers: Gorgon, Hydra, Basilisk, and Manticore. The Maw's secret existence was exposed after Han Solo and Kyp Durron, fleeing the nearby Kessel, found themselves inside the cluster. The installation was left undefended for a time, as Daala went on a brief guerilla assault on the New Republic. It was later destroyed in a self-destruct, but not before Daala returned and stole all the new weapons concepts from the main computer. 
The installation's fragments were later used to build Shelter, a Jedi facility located in the installation's former position.