Unroth III was a Romulan colony world in the Unroth system in the Onias Sector near the border with the Cardassian Union. (ST reference: Star Charts, ENT novel: The Good That Men Do)
Sometime prior to the planet's colonization, the Romulan Star Empire set up a cloaked minefield very close to the planet. In 2152, the Earth Starfleet vessel Enterprise (NX-01) unknowingly entered the field, suffering heavy damage before being warned to leave. V'Las sent a report to his handlers about the incident. By this time, there was an abandoned outpost on the world. (ENT episode: "Minefield", ST reference: Federation: The First 150 Years)
- The planet being in vicinity of the minefield was not mentioned in the episode, but was stated in the reference work Federation: The First 150 Years.
During the Dominion War, Dominion forces planned an attack on the colony upon discovering that the planet's long-range scanners were under repair. (DS9 episode: "Strange Bedfellows")
