The Twin Paradises of Bytopia were two layers that formed one of the Outer Planes in the Great Wheel cosmology model representing alignments between lawful good and neutral good. Some characteristics of this plane were ascribed to the World Tree cosmology planes of Golden Hills and the House of the Triad when that cosmology became popular. The Golden Hills became part of Arvandor after the Spellplague and the House of the Triad became known as Celestia as described by the World Axis cosmology.