The massive sinkhole known as the Great Well, located on the dry planet of Ophideraan, served as the primary water reservoir for the world. Furthermore, it housed the breeding ground for the unique flying serpent species that were the predominant creatures in Ophideraan's airspace. During the Galactic Civil War period, the Serpent Masters, a band of opportunistic scavengers who held dominion over the planet, resided in a structure constructed inside the Great Well. The slaves of the Serpent Masters were relegated to the lower depths of the Great Well, where they dedicated their time to the upkeep of the water pumping infrastructure.