Alta

Alta uses beam tethers to allow spaceships of all kinds to dock, which provide power to the ships and enables them to join movement to the disc's without expending fuel.

From much of Alta, individuals can see space through two magical forcefields, onewhich provides breathable air to the organic inhabitants of the city and one which protects everything, including docked ships, from asteroids that may fly through gates.  It is difficult to determine where the permanent and transient gates in space are, but ship navigators make use of a network of comm buoys to detect where the permanent gates are and to stay apprised of the locations of new transient gates.

Alta has numerous warehouses, including some beyond the forcefield that provides air to the city.  Not every good brought in can be stored in an oxygen rich environment, after all.  They're not much of a tourist destination, but are far more a shortcut for spaceship captains to get between different solar systems much quicker than they could travel from their own system to a different system.