Selonia is an oceanic planet in the Corellian system. It is one of the Five Brothers of the Corellian system (the others being Corellia, Drall and the twin worlds of Tralus and Talus) and served as the homeworld of the Selonians.
An industrial world comprised of many small islands and surrounded by a global ocean, the native Selonians dug an elaborate network of tunnels under the planetary surface in order to successfully facilitate contact among their peoples.
These Selonian "dens" and tunnels ran through much of the planet's crust and mantle, while orbital shipyards operated above the planet. Most of the vessels produced over Selonia were constructed for use within the Corellian system and, since Selonians generally had little interest in exploring further, were not fitted with hyperdrives.