Polerica is an island that flies through the sky, never staying in one place but constantly floating over the globe. How is this possible? It uses no engines or repulsors, and how could it, for it was around long before any such things were invented.
The fact is that Polerica remains airborne thanks to the nature of the people who inhabit it. The residents of Polerica all have a racial feature known as an Echo Organ, which allows them to float through the air if they do not talk. Polerica has been built in such a way that it harnesses these energies and floats by itself.
People who aren't Polerican can join it easily. Once they have grown their own Echo Organs, they will find themselves spouting all kinds of crap naturally. This is automatic, but if they purposefully stop talking for long enough they will find themselves rising through the air. Sooner or later Polerica will fly by and pick them up, adding these people to their population.
But what's the purpose of making Polerica float through the air, anyway? Well, as can be imagined, people with Echo Organs and Polericans in general are universally dreaded. Polerica gives them a place where they can be themselves, hang out with similar minds (blank ones, that is), and escape the persecution of people who want interesting conversations and serious thought.