Sunbars are large holes between buildings in the slums of Sectors 5 and 6 that go almost all the way to the bottom, to allow light from the sun to pass through onto the lower levels of the slums. They vary in shape and size, ranging from 2.5 to 25 meters in diameter. Sunbars usually get smaller the further down in the slums they are, and will typically have grates or transparent glass allowing people to cross them safely.
Gangs in Sector 6 have been known to cover up various Sunbars using large tarps or sheet metal, or even build farms across them. The reason for this, is so people further down in the slums cannot grow their own food in the sunlight, forcing the citizens hands into the gangs economies in order to survive.