Gamma Hydra

Gamma Hydra was the primary of the uninhabited Gamma Hydra system located in the Alpha Quadrant. A planet in this system, Gamma Hydra IV, was the site of a Federation experimental colony in the mid-23rd century. This system was located in the Gamma Hydra sector, which was proximal to both the Romulan, and the Klingon Neutral Zone, as well as Starbase 10 and Outpost 4. (, display graphic)

In the Kobayashi Maru training scenario with Lieutenant Saavik, the USS Enterprise (NCC-1701) had entered into Section 14 when the ship received a distress call from the Kobayashi Maru which was in Section 10. 

In 2367, the star appeared on a chart in Captain Benjamin Maxwell's ready room on the USS Phoenix. (, display graphic)

In an alternate timeline, in 2366, Gamma Hydra was mentioned on a tactical display seen in the observation lounge, showing the Klingon progress in their war with the Federation. ( display graphic)