Bytopia (fictional land)

In the Dungeons & Dragons Planescape setting, Bytopia is the Twin Paradises (bi- + utopia). People of Neutral Good Lawful alignment are reborn as petitioners here after death.

Bytopia has two layers:

Dothion
Shurrock

Bytopia is unique in the sense that a traveller can look up from one layer and see the other above him, provided that the sky is clear. To get from one layer to the other, travellers must either climb tall mountains, or fly. Gravity reverses when someone reaches the middle point between the two layers.