Topopolis
Picture a giant tube world stretching for millions of kilometers through space.
People wouldn’t live on planets anymore… they’d live inside a rotating cylinder so vast, it becomes a civilization of its own.
The entire inner surface could be covered with cities, forests, oceans, and artificial skies.
As the structure rotates, centrifugal force would create artificial gravity, allowing people to walk, build, and live along its inner walls.
Sunlight could be directed inside using massive mirrors, creating artificial days and nights.
But a Topopolis wouldn’t be the size of a city… or even a planet.
In theory, this megastructure could loop around a star or stretch across an entire star system.
Billions… perhaps trillions of humans could live inside.
Earth would no longer be humanity’s only home.
The civilization itself would become a world.
This is the Topopolis… one of the most extreme megastructures ever imagined.
