The System of the Spheres

The System of the Spheres (or the Seven, or variations thereon) is the inhabitants' name for a rogue star in intergalactic space that, instead of planets, is enclosed by multiple completely solid Dyson spheres. All evidence suggests that the system was artificially created and artificially maintained, but how and by whom are still unknown.

The System
For centuries, a stable, solid Dyson sphere was held to be impossible, even by Freeman Dyson, whose actual concept was of a gargantuan version of the Klargg Swarm that completely surrounded its star. The System consists of seven, nested in each other like a giant matryoshka doll set. When the System was discovered by the Second Terrestrial Empire, several prominent astrophysicists drove themselves mad trying to explain its complexities.

The Spheres
There are seven spheres in the system; both faces of each sphere are inhabited.

Reference Districts
Each sphere's face is split by force-fields of an unknown and un-analysable nature into what the inhabitants call "Reference Districts", or "RDs". These RDs are each approximately 200 million square miles in area.

The First Sphere
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The Second Sphere
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The Third Sphere
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The Fourth Sphere
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The Fifth Sphere
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The Sixth Sphere
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The Seventh Sphere
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Real-World Stuff
This is the major playground for rpg campaign settings, as the sheer scale of the spheres allows for, wait for it, Endless Adventures.