Taurus Reach
The Taurus Reach was a region of space adjacent to the territory of the United Federation of Planets, the Klingon Empire (who refered to the region as the Gonmog Sector), and the Tholian Assembly (who called it the Shedai Sector). This was considered a strategically important sector of space by all three powers in the mid-23rd century. In 2265, the Federation had begun aggressively establishing colonies within the Taurus Reach, and Starfleet commissioned a Watchtower-class starbase (Starbase 47, or Vanguard) in order to support and defend these new settlements.
The Taurus Reach was also the location of the planet Ravanar IV, which was visited by the USS Constellation in 2263, and was the site of the destruction of the USS Bombay in 2265.
List of Worlds in or Near the Taurus Reach
Mirror Universe
In the Mirror Universe the Taurus Reach was a region of very aggressive Imperial expansion. The Terran Empire controlled the area from Imperial Starbase 47, which was commanded by Commodore Diego "Red" Reyes. In 2277, an operative loyal to Spock initiated plans to eliminate the Empire's presence in that region.