Port Maw System

The Port Maw System is the Gothic Sector's naval capital well, a hollow artificial planetoid whose five-hundred-kilometre aperture gave the station its name. The 60th Expedition found it in the Coronid Deeps; Terra ordered a northern fleet fortress built inside.

Traitor officers later turned its panopticon on assembling loyalists in the Heresy. In the Gothic War the station sat impregnable behind mines and forts while Chaos blockaded it rather than storming the hole. The child pin is the station, not a hive world.

The Port Maw System still matters as the Gothic Navy's mouth. Unofficial fan summaries keep the Port Maw Sub-sector parent and refuse to treat the aperture as a natural planet.