Ch'Mrelkhre, which when translated from Rihannsu meant "the small end of the funnel", was a space station that existed by the 23rd century and was also known as Omega.
It was a border station that was placed within the Romulan Neutral Zone though it was set up on the United Federation of Planets edge of space by terms of the Earth-Romulan treaty which were signed a century before during the War. Known to Starfleet as Omega, the station was an uneasy amalgamation of Romulan and Human space architecture that was constructed in the spirit of competition rather than cooperation. The location meant it was perched precariously in between the Neutral Zone and was constantly patrolled by ships from either side. It was known as up to several hundred beings passed daily through the no man's land of umbilicals between the two halves of the station which were carefully screened by sentries from either government.
In 2293, Hikaru Sulu infiltrated ch'Mrelhre during the crisis when the Warrantors of the Peace were kidnapped by the Romulan government. (TOS novel: Dwellers in the Crucible)