The Rihet Ruins are the remains of an ancient factory (not unlike Grabad), used as an exploration location in Monster Rancher Battle Card. It sits on the northwest side of Aurora Island, in the midst of the Morx Forest. It has alot of pipes, conveyor belts and metal grates, and it may be much like the Melcarba manufacturing plant that the Searchers stumble into on the anime show.
The outside has several metal and stone towers, but much of the factory is underground. Assembly lines were run by computers.