Freeport Nebula

Freeport Nebula is known as a rally point and safe haven for pirates and black market smugglers. Their ships seem to be able to disappear once inside. Many fleets were sent to hunt them there but could never find them.
The known secret among the pirates of is the dimensional bleed that is on one of the planets. They have learned of a technology that allows them to open the bleed and pull their ships inside into the other dimension. There, all outlaws hide and tolerate each other out of fear of loosing this sanctuary.  They don't understand the tech and no idea of fighting broke out among rivals could collapse the dimensional bleed trapping them in the alien dimension or trapped out of it allowing the bounty hunters and military ships to find them. 
This lawless place had some issues at first, but the smarter of the pirates found a way to get everyone to agree on procedures of when to open and close the bleed.  There was one occasion that the bleed was almost seen from the authorities and all the pirates put the crew of the ship responsible on trial and found the first mate at fault and executed them.  
As piratcy became less prosperous, Freeport became more focus on black market trades, but still was a way for some criminals to hide.  Eventually, less respectable bounty hunters started to enter the bleed through bribes to hunt the for easy pay that no other criminals care about.  They were even hired by cartels to get rid of trouble makers or who ripped off the wrong people.  
Eventually, a High Tech Inquisitor found the dimensional bleed and recognize the tech and sent a message throughout the Nebula demanding the tech be handed over and any schematics involving the tech.  They refused, and for the first time in a long time faced the wrath of a Reaper.  Freeport was abandoned and what tech the inquisition could find was destroyed and the dimensional bleed is under study to see if the All-Mother left that bleed for a reason or if the pirates created it and needs to be destroyed.

Type

Nebula