According to abhidharma cosmology, when different world systems form, they drift near each other, but remain divided by the spaces (small according to some descriptions, immense according to others) between the massive rings of stone that surround each of them. These spaces are completely dark, unreached by any light from the suns of the worlds they lie between. Often classified as one kind of hell, these frigid and desolate places are populated by beings brought there by very negative karma. They cling to the cliffs, climbing around in darkness searching for sustenance. When they encounter fellow sufferers, they fight and try to push each other off, and tumble into the icy waters below.