Tambor was a star system, located in 23rd century Tholian Assembly space, near the Klingon Empire's borders, somewhere in the galaxy's Alpha Quadrant.
History and specifics
The Tambor system's orbit was the location of two planets. (ST video game: Klingon Academy)
In an Imperial Klingon Star Academy combat training simulation, the USS Fesoan escaped to the Tambor system to protect Federation Ambassador M'Giia from a Klingon raid. (ST video game: Klingon Academy, Mission 8)