- Recreation Center
- Commerce Center
- One or more Standard Passenger Compartments or Massive Passenger Compartments.
While they can be built anywhere, they are intended to be built at locations with Ruins or a Scenery Bonus - the simple blackness of space may be minimally interesting, but a Black Hole eating away at a nebula is much more so. Such Scenery Bonuses are, of course, listed in the selection description alongside any Ruins.