Sector 16C was a region of space, a sector located in the galaxy's Alpha or Beta Quadrant, and was a location on star charts used by the Federation in the 23rd century.
History and specifics[]
The star Hydra was located in Sector 16C.
In the early 2230s, the sector was explored by the Mann-class starship USS Poseidon. (ST reference: Spaceflight Chronology)