Federation-Klingon border
From Memory Alpha, the free Star Trek reference
The Federation-Klingon border was the division between the United Federation of Planets and the Klingon Empire.
Deep Space K-7 was located near the border in the 23rd century. (TOS: "The Trouble with Tribbles"; DS9: "Trials and Tribble-ations")
Following Chancellor Gowron's demand for the Federation to leave the Archanis sector, several representatives from planets on the Federation side of the border urged a preemptive strike on the Klingons. (DS9: "Broken Link")
