The Bubble is a sphere of about 150 light years around Sol with approximately 19 thousand inhabited systems where powers compete for influence, resources, territory and control. The territory volume is about 13.8 million cubic light years. It's also known as the Core Worlds.
Human settlements are rare the further away you go from the Bubble. There are smaller populated regions like Colonia which is 22,000 light years from the Bubble. It can be reached via the Colonia Connection Highway. Dozens of Asteroid Bases exist in deep space.