The Lower Planes was a collective term used in the Great Wheel Cosmology model to represent the Outer Planes of Evil alignment, located across the bottom of the Great Wheel. These were Acheron, the Nine Hells, Gehenna, Hades, Tarterus, the Abyss, and Pandemonium. The only other thing these planes have in common is the River Styx which flows through at least one level of each Evil Plane.
