Tower Hoc was once the headquarters for the exiled Thessan archmage Ripwald. The archmage's experiments with World Cavern magics and dealings with dark elves drew the ire of the Thessan council and he was exiled from the Dukedom. Ripwald traveled South into the unclaimed land between Yod and the Ibyth Imperium and built a small tower on the coast of Yurtur's Cauldon in The Pendants. Several decades passed after the archmage was last seen and the tower fell into the hands of the Unsung Heros. When they eventually parted ways, ownership of the tower passed to Joman, who, now going by the name Jod, married into the Shay family and the tower became the family home of the Hoc Shay's. In the 5th age, a small farming community had developed around the Tower, trading surface goods with the denizens of the subterranean realms.
The tower houses many arcane devices and experiments left by its previous owner. The Gravity Well is one of them, a massive circular tunnel bored straight down into the World Cavern. The arcane enchantments sewn into the wall reduce falling speed so that a person can simply fall to the bottom or leap to the top without issue, granting easy access to the subterranean realm. This proved to be exceedingly dangerous as no one can predict what horrors may wander out of the dark abyss.