Starbase 25

Starbase 25 was a Starfleet starbase in operation in the mid 23rd century.

In 2270, the Shuttlecraft Copernicus set course for Starbase 25, transporting a Slaver stasis box. 

At some point, the crew of Starbase 25 studied a recovered Preserver space buoy. (TOS reference: Who's Who in Star Trek)