Khitomer is a Class M planet located in the Khitomer system in the Beta Quadrant. Khitomer played a vital role in the development of the Klingon-Federation alliance, being the site of the Khitomer Conference and the victim of a Romulan sneak attack on this planet's colony, which, in turn, emphasized the importance of the Klingon-Federation friendship. (TNG: "The Neutral Zone", "Sins of the Father")
In 2293, Khitomer was considered to be a neutral site between the Federation and the Klingon Empire, and was located near the Romulan border. In that year, the Khitomer Conference was held at Camp Khitomer on the planet. The conference started the first full peace negotiations between the United Federation of Planets and the Klingon Empire and gave birth to the Khitomer Accords. Originally, Earth had been selected as a venue, but after Klingon Chancellor Gorkon was assassinated on his way to Earth, the conference had to be relocated to Camp Khitomer. (Star Trek VI: The Undiscovered Country)
The Romulan Empire thereafter laid claim to the planet, and it appeared on Federation maps in 2369 as being within their territory. (TNG: "Birthright, Part II")
Some time prior to 2375, Admiral William Ross met Chancellor Gowron at Khitomer. (DS9: "When It Rains...")
- The exact status of Khitomer – under whose sphere of influence it falls – at the time of the conference is never made clear. The Star Trek Encyclopedia states it to be "near the Romulan/Klingon border", but whether it was claimed by either empire at the time is left unsaid. However, it would seem unlikely to be considered "a neutral site" in either case.