The Cestus system is a star system located in Federation space near the border with the Gorn Hegemony, on the opposite side of the Federation from Deep Space 9. It is also near space claimed by the Metrons. (TOS: "Arena"; DS9: "Family Business")

In the late 23rd century, the system was on the frontier of Federation space. The Gorn were alarmed by the establishment of a Federation colony in this system on Cestus III, as they regarded the system as part of their territory. In 2267 a Gorn vessel entered the system, and the Captain led an assault on the colony, destroying it and its inhabitants.

They then sent a fake distress call to lure the USS Enterprise into the system, and then a ground team onto the surface of the planet. At this point, the Metrons intervened and forced the two Captains to do battle with each other on Cestus III. (TOS: "Arena")

By the late 24th century, the Federation had reestablished a colony on Cestus III. (DS9: "Family Business", "The Way of the Warrior")

• Cestus (primary)
  • Cestus I
  • Cestus II
  • Cestus III