Nel III was one of two inhabited planets in the Epsilon Nel system. By 2368, the cities on this planet included Alpha Municipality, Grant Municipality, and Epsilon Municipality. Two of the medical facilities on this planet were the Goodhartz Medical Facility and Farrell Hospital.
This planet was one of eleven visited by a group of Ullian telepathic historians in the 2360s, who collected a library of memories from the inhabitants. Soon after the visit, the planet reported two unexplained comas. The comas were later determined to be a result of telepathic memory invasion perpetuated byJev. A person of interest in the case, Tarmin, was exonerated as he was on his species' homeworld at the time of the visit. (TNG: "Violations")
In the pre-remastered episode, Gray Municipality was a city on this planet, and the two medical facilities were the Taylor Hospital and Wiemer Medical Facility.