Ab-Tzenketh

Tzenketh is the homeworld of the Tzenkethi species and the administrative centre of the Tzenkethi Coalition.

Starbase 621 is located nearby. The planet Mizar is also not particularly distant. (Star Trek: Star Charts)

Elim Garak once travelled to the planet while working for the Obsidian Order. While undertaking the mission, the walls of the building he was in collapsed around him. (DS9 episode: "By Inferno's Light")